pymatgen.electronic_structure package
This package contains electronic structure related tools and analyses.
Submodules
pymatgen.electronic_structure.bandstructure module
This module provides classes to define everything related to band structures.
- class BandStructure(kpoints: ndarray, eigenvals: dict[Spin, ndarray], lattice: Lattice, efermi: float, labels_dict=None, coords_are_cartesian: bool = False, structure: Structure | None = None, projections: dict[Spin, ndarray] | None = None)[source]
Bases:
object
This is the most generic band structure data possible it’s defined by a list of kpoints + energies for each of them.
- bands[source]
The energy eigenvalues as a {spin: array}. Note that the use of an array is necessary for computational as well as memory efficiency due to the large amount of numerical data. The indices of the array are [band_index, kpoint_index].
- Type:
dict
- projections[source]
The projections as a {spin: array}. Note that the use of an array is necessary for computational as well as memory efficiency due to the large amount of numerical data. The indices of the array are [band_index, kpoint_index, orbital_index, ion_index].
- Type:
dict
- Parameters:
kpoints – list of kpoint as numpy arrays, in frac_coords of the given lattice by default
eigenvals – dict of energies for spin up and spin down {Spin.up:[][],Spin.down:[][]}, the first index of the array [][] refers to the band and the second to the index of the kpoint. The kpoints are ordered according to the order of the kpoints array. If the band structure is not spin polarized, we only store one data set under Spin.up
lattice – The reciprocal lattice as a pymatgen Lattice object. Pymatgen uses the physics convention of reciprocal lattice vectors WITH a 2*pi coefficient
efermi (float) – fermi energy
labels_dict – (dict) of {} this links a kpoint (in frac coords or Cartesian coordinates depending on the coords) to a label.
coords_are_cartesian – Whether coordinates are cartesian.
structure – The crystal structure (as a pymatgen Structure object) associated with the band structure. This is needed if we provide projections to the band structure
projections – dict of orbital projections as {spin: array}. The indices of the array are [band_index, kpoint_index, orbital_index, ion_index].If the band structure is not spin polarized, we only store one data set under Spin.up.
- classmethod from_dict(dct: dict) Self [source]
Create from dict.
- Parameters:
dct – A dict with all data for a band structure object.
- Returns:
A BandStructure object
- classmethod from_old_dict(dct)[source]
- Parameters:
dct (dict) – A dict with all data for a band structure symmetry line object.
- Returns:
A BandStructureSymmLine object
- get_band_gap()[source]
Returns band gap data.
- Returns:
“energy”: band gap energy “direct”: A boolean telling if the gap is direct or not “transition”: kpoint labels of the transition (e.g., “\Gamma-X”)
- Return type:
A dict {“energy”,”direct”,”transition”}
- get_cbm()[source]
Returns data about the CBM.
- Returns:
- with keys band_index, kpoint_index, kpoint, energy.
”band_index”: A dict with spin keys pointing to a list of the
indices of the band containing the CBM (please note that you can have several bands sharing the CBM) {Spin.up:[], Spin.down:[]} - “kpoint_index”: The list of indices in self.kpoints for the kpoint CBM. Please note that there can be several kpoint_indices relating to the same kpoint (e.g., Gamma can occur at different spots in the band structure line plot) - “kpoint”: The kpoint (as a kpoint object) - “energy”: The energy of the CBM - “projections”: The projections along sites and orbitals of the CBM if any projection data is available (else it is an empty dictionary). The format is similar to the projections field in BandStructure: {spin:{‘Orbital’: [proj]}} where the array [proj] is ordered according to the sites in structure
- Return type:
dict[str, Any]
- get_direct_band_gap()[source]
Returns the direct band gap.
- Returns:
the value of the direct band gap
- get_direct_band_gap_dict()[source]
Returns a dictionary of information about the direct band gap.
- Returns:
a dictionary of the band gaps indexed by spin along with their band indices and k-point index
- get_kpoint_degeneracy(kpoint, cartesian=False, tol: float = 0.01)[source]
Returns degeneracy of a given k-point based on structure symmetry.
- Parameters:
kpoint (1x3 array) – coordinate of the k-point
cartesian (bool) – kpoint is in Cartesian or fractional coordinates
tol (float) – tolerance below which coordinates are considered equal.
- Returns:
degeneracy or None if structure is not available
- Return type:
int | None
- get_projection_on_elements()[source]
Method returning a dictionary of projections on elements.
- Returns:
[][{Element:values}], Spin.down:[][{Element:values}]} format if there is no projections in the band structure returns an empty dict
- Return type:
a dictionary in the {Spin.up
- get_projections_on_elements_and_orbitals(el_orb_spec)[source]
Method returning a dictionary of projections on elements and specific orbitals.
- Parameters:
el_orb_spec – A dictionary of Elements and Orbitals for which we want to have projections on. It is given as: {Element:[orbitals]}, e.g., {‘Cu’:[‘d’,’s’]}
- Returns:
A dictionary of projections on elements in the {Spin.up:[][{Element:{orb:values}}], Spin.down:[][{Element:{orb:values}}]} format if there is no projections in the band structure returns an empty dict.
- get_sym_eq_kpoints(kpoint, cartesian=False, tol: float = 0.01)[source]
Returns a list of unique symmetrically equivalent k-points.
- Parameters:
kpoint (1x3 array) – coordinate of the k-point
cartesian (bool) – kpoint is in Cartesian or fractional coordinates
tol (float) – tolerance below which coordinates are considered equal
- Returns:
if structure is not available returns None
- Return type:
list[1x3 array] | None
- get_vbm()[source]
Returns data about the VBM.
- Returns:
With keys “band_index”, “kpoint_index”, “kpoint”, “energy” - “band_index”: A dict with spin keys pointing to a list of the indices of the band containing the VBM (please note that you can have several bands sharing the VBM) {Spin.up:[], Spin.down:[]} - “kpoint_index”: The list of indices in self.kpoints for the kpoint VBM. Please note that there can be several kpoint_indices relating to the same kpoint (e.g., Gamma can occur at different spots in the band structure line plot) - “kpoint”: The kpoint (as a kpoint object) - “energy”: The energy of the VBM - “projections”: The projections along sites and orbitals of the VBM if any projection data is available (else it is an empty dictionary). The format is similar to the projections field in BandStructure: {spin:{‘Orbital’: [proj]}} where the array [proj] is ordered according to the sites in structure
- Return type:
dict
- class BandStructureSymmLine(kpoints, eigenvals, lattice, efermi, labels_dict, coords_are_cartesian=False, structure=None, projections=None)[source]
Bases:
BandStructure
,MSONable
This object stores band structures along selected (symmetry) lines in the Brillouin zone. We call the different symmetry lines (ex: \Gamma to Z) “branches”.
- Parameters:
kpoints – list of kpoint as numpy arrays, in frac_coords of the given lattice by default
eigenvals – dict of energies for spin up and spin down {Spin.up:[][],Spin.down:[][]}, the first index of the array [][] refers to the band and the second to the index of the kpoint. The kpoints are ordered according to the order of the kpoints array. If the band structure is not spin polarized, we only store one data set under Spin.up.
lattice – The reciprocal lattice. Pymatgen uses the physics convention of reciprocal lattice vectors WITH a 2*pi coefficient
efermi – fermi energy
labels_dict – (dict) of {} this link a kpoint (in frac coords or Cartesian coordinates depending on the coords).
coords_are_cartesian – Whether coordinates are cartesian.
structure – The crystal structure (as a pymatgen Structure object) associated with the band structure. This is needed if we provide projections to the band structure.
projections – dict of orbital projections as {spin: array}. The indices of the array are [band_index, kpoint_index, orbital_index, ion_index].If the band structure is not spin polarized, we only store one data set under Spin.up.
- apply_scissor(new_band_gap)[source]
Apply a scissor operator (shift of the CBM) to fit the given band gap. If it’s a metal, we look for the band crossing the Fermi level and shift this one up. This will not work all the time for metals!
- Parameters:
new_band_gap – the band gap the scissor band structure need to have.
- Returns:
with the applied scissor shift
- Return type:
- get_branch(index)[source]
Returns in what branch(es) is the kpoint. There can be several branches.
- Parameters:
index – the kpoint index
- Returns:
A list of dictionaries [{“name”,”start_index”,”end_index”,”index”}] indicating all branches in which the k_point is. It takes into account the fact that one kpoint (e.g., \Gamma) can be in several branches
- get_equivalent_kpoints(index)[source]
Returns the list of kpoint indices equivalent (meaning they are the same frac coords) to the given one.
- Parameters:
index – the kpoint index
- Returns:
a list of equivalent indices
TODO: now it uses the label we might want to use coordinates instead (in case there was a mislabel)
- class Kpoint(coords: ndarray, lattice: Lattice, to_unit_cell: bool = False, coords_are_cartesian: bool = False, label: str | None = None)[source]
Bases:
MSONable
Class to store kpoint objects. A kpoint is defined with a lattice and frac or Cartesian coordinates syntax similar than the site object in pymatgen.core.structure.
- Parameters:
coords – coordinate of the kpoint as a numpy array
lattice – A pymatgen.core.Lattice object representing the reciprocal lattice of the kpoint
to_unit_cell – Translates fractional coordinate to the basic unit cell, i.e., all fractional coordinates satisfy 0 <= a < 1. Defaults to False.
coords_are_cartesian – Boolean indicating if the coordinates given are in Cartesian or fractional coordinates (by default fractional)
label – the label of the kpoint if any (None by default).
- class LobsterBandStructureSymmLine(kpoints, eigenvals, lattice, efermi, labels_dict, coords_are_cartesian=False, structure=None, projections=None)[source]
Bases:
BandStructureSymmLine
Lobster subclass of BandStructure with customized functions.
- Parameters:
kpoints – list of kpoint as numpy arrays, in frac_coords of the given lattice by default
eigenvals – dict of energies for spin up and spin down {Spin.up:[][],Spin.down:[][]}, the first index of the array [][] refers to the band and the second to the index of the kpoint. The kpoints are ordered according to the order of the kpoints array. If the band structure is not spin polarized, we only store one data set under Spin.up.
lattice – The reciprocal lattice. Pymatgen uses the physics convention of reciprocal lattice vectors WITH a 2*pi coefficient
efermi – fermi energy
labels_dict – (dict) of {} this link a kpoint (in frac coords or Cartesian coordinates depending on the coords).
coords_are_cartesian – Whether coordinates are cartesian.
structure – The crystal structure (as a pymatgen Structure object) associated with the band structure. This is needed if we provide projections to the band structure.
projections – dict of orbital projections as {spin: array}. The indices of the array are [band_index, kpoint_index, orbital_index, ion_index].If the band structure is not spin polarized, we only store one data set under Spin.up.
- classmethod from_dict(dct: dict) Self [source]
- Parameters:
dct (dict) – A dict with all data for a band structure symmetry line object.
- Returns:
A BandStructureSymmLine object
- classmethod from_old_dict(dct)[source]
- Parameters:
dct (dict) – A dict with all data for a band structure symmetry line object.
- Returns:
A BandStructureSymmLine object
- get_projection_on_elements()[source]
Method returning a dictionary of projections on elements. It sums over all available orbitals for each element.
- Returns:
[][{Element:values}], Spin.down:[][{Element:values}]} format if there is no projections in the band structure returns an empty dict
- Return type:
a dictionary in the {Spin.up
- get_projections_on_elements_and_orbitals(el_orb_spec)[source]
Method returning a dictionary of projections on elements and specific orbitals.
- Parameters:
el_orb_spec – A dictionary of Elements and Orbitals for which we want to have projections on. It is given as: {Element:[orbitals]}, e.g., {‘Si’:[‘3s’,’3p’]} or {‘Si’:[‘3s’,’3p_x’, ‘3p_y’, ‘3p_z’]} depending on input files
- Returns:
A dictionary of projections on elements in the {Spin.up:[][{Element:{orb:values}}], Spin.down:[][{Element:{orb:values}}]} format if there is no projections in the band structure returns an empty dict.
- get_reconstructed_band_structure(list_bs, efermi=None)[source]
This method takes a list of band structures and reconstructs one band structure object from all of them.
This is typically very useful when you split non self consistent band structure runs in several independent jobs and want to merge back the results
- Parameters:
list_bs – A list of BandStructure or BandStructureSymmLine objects.
efermi – The Fermi energy of the reconstructed band structure. If None is assigned an average of all the Fermi energy in each object in the list_bs is used.
- Returns:
A BandStructure or BandStructureSymmLine object (depending on the type of the list_bs objects)
pymatgen.electronic_structure.boltztrap module
This module provides classes to run and analyze boltztrap on pymatgen band structure objects. Boltztrap is a software interpolating band structures and computing materials properties from this band structure using Boltzmann semi-classical transport theory.
Boltztrap has been developed by Georg Madsen.
http://www.icams.de/content/research/software-development/boltztrap/
You need version 1.2.3 or higher
References are:
Madsen, G. K. H., and Singh, D. J. (2006). BoltzTraP. A code for calculating band-structure dependent quantities. Computer Physics Communications, 175, 67-71
- class BoltztrapAnalyzer(gap=None, mu_steps=None, cond=None, seebeck=None, kappa=None, hall=None, doping=None, mu_doping=None, seebeck_doping=None, cond_doping=None, kappa_doping=None, hall_doping=None, intrans=None, dos=None, dos_partial=None, carrier_conc=None, vol=None, warning=None, bz_bands=None, bz_kpoints=None, fermi_surface_data=None)[source]
Bases:
object
Class used to store all the data from a boltztrap run.
Constructor taking directly all the data generated by Boltztrap. You won’t probably use it directly but instead use the from_files and from_dict methods.
- Parameters:
gap – The gap after interpolation in eV
mu_steps – The steps of electron chemical potential (or Fermi level) in eV.
cond – The electronic conductivity tensor divided by a constant relaxation time (sigma/tau) at different temperature and fermi levels. The format is {temperature: [array of 3x3 tensors at each Fermi level in mu_steps]}. The units are 1/(Ohm*m*s).
seebeck – The Seebeck tensor at different temperatures and fermi levels. The format is {temperature: [array of 3x3 tensors at each Fermi level in mu_steps]}. The units are V/K
kappa – The electronic thermal conductivity tensor divided by a constant relaxation time (kappa/tau) at different temperature and fermi levels. The format is {temperature: [array of 3x3 tensors at each Fermi level in mu_steps]} The units are W/(m*K*s)
hall – The hall tensor at different temperature and fermi levels The format is {temperature: [array of 27 coefficients list at each Fermi level in mu_steps]} The units are m^3/C
doping – The different doping levels that have been given to Boltztrap. The format is {‘p’:[],’n’:[]} with an array of doping levels. The units are cm^-3
mu_doping – Gives the electron chemical potential (or Fermi level) for a given set of doping. Format is {‘p’:{temperature: [fermi levels],’n’:{temperature: [fermi levels]}} the Fermi level array is ordered according to the doping levels in doping units for doping are in cm^-3 and for Fermi level in eV
seebeck_doping – The Seebeck tensor at different temperatures and doping levels. The format is {‘p’: {temperature: [Seebeck tensors]}, ‘n’:{temperature: [Seebeck tensors]}} The [Seebeck tensors] array is ordered according to the doping levels in doping units for doping are in cm^-3 and for Seebeck in V/K
cond_doping – The electronic conductivity tensor divided by a constant relaxation time (sigma/tau) at different temperatures and doping levels The format is {‘p’:{temperature: [conductivity tensors]}, ‘n’:{temperature: [conductivity tensors]}} The [conductivity tensors] array is ordered according to the doping levels in doping units for doping are in cm^-3 and for conductivity in 1/(Ohm*m*s)
kappa_doping – The thermal conductivity tensor divided by a constant relaxation time (kappa/tau) at different temperatures and doping levels. The format is {‘p’:{temperature: [thermal conductivity tensors]},’n’:{temperature: [thermal conductivity tensors]}} The [thermal conductivity tensors] array is ordered according to the doping levels in doping units for doping are in cm^-3 and for thermal conductivity in W/(m*K*s)
hall_doping – The Hall tensor at different temperatures and doping levels. The format is {‘p’:{temperature: [Hall tensors]}, ‘n’:{temperature: [Hall tensors]}} The [Hall tensors] array is ordered according to the doping levels in doping and each Hall tensor is represented by a 27 coefficients list. The units are m^3/C
intrans – a dictionary of inputs e.g. {“scissor”: 0.0}
carrier_conc – The concentration of carriers in electron (or hole) per unit cell
dos – The dos computed by Boltztrap given as a pymatgen Dos object
dos_partial – Data for the partial DOS projected on sites and orbitals
vol – Volume of the unit cell in angstrom cube (A^3)
warning – string if BoltzTraP outputted a warning, else None
bz_bands – Data for interpolated bands on a k-point line (run_type=BANDS)
bz_kpoints – k-point in reciprocal coordinates for interpolated bands (run_type=BANDS)
fermi_surface_data – energy values in a 3D grid imported from the output .cube file.
- static check_acc_bzt_bands(sbs_bz, sbs_ref, warn_thr=(0.03, 0.03))[source]
Compare sbs_bz BandStructureSymmLine calculated with boltztrap with the sbs_ref BandStructureSymmLine as reference (from MP for instance), computing correlation and energy difference for eight bands around the gap (semiconductors) or Fermi level (metals). warn_thr is a threshold to get a warning in the accuracy of Boltztap interpolated bands.
Return a dictionary with these keys: - “N”: the index of the band compared; inside each there are:
“Corr”: correlation coefficient for the 8 compared bands
“Dist”: energy distance for the 8 compared bands
“branch_name”: energy distance for that branch
“avg_corr”: average of correlation coefficient over the 8 bands
“avg_dist”: average of energy distance over the 8 bands
“nb_list”: list of indexes of the 8 compared bands
“acc_thr”: list of two float corresponding to the two warning thresholds in input
- “acc_err”: list of two bools:
True if the avg_corr > warn_thr[0], and True if the avg_dist > warn_thr[1]
See also compare_sym_bands function doc.
- classmethod from_dict(data: dict) Self [source]
- Parameters:
data – Dict representation.
- Returns:
BoltztrapAnalyzer
- classmethod from_files(path_dir, dos_spin=1)[source]
Get a BoltztrapAnalyzer object from a set of files.
- Parameters:
path_dir – directory where the boltztrap files are
dos_spin – in DOS mode, set to 1 for spin up and -1 for spin down
- Returns:
a BoltztrapAnalyzer object
- get_average_eff_mass(output='eigs', doping_levels=True)[source]
Gives the average effective mass tensor. We call it average because it takes into account all the bands and regions in the Brillouin zone. This is different than the standard textbook effective mass which relates often to only one (parabolic) band. The average effective mass tensor is defined as the integrated average of the second derivative of E(k) This effective mass tensor takes into account: -non-parabolicity -multiple extrema -multiple bands.
For more information about it. See:
Hautier, G., Miglio, A., Waroquiers, D., Rignanese, G., & Gonze, X. (2014). How Does Chemistry Influence Electron Effective Mass in Oxides? A High-Throughput Computational Analysis. Chemistry of Materials, 26(19), 5447-5458. doi:10.1021/cm404079a
or
Hautier, G., Miglio, A., Ceder, G., Rignanese, G.-M., & Gonze, X. (2013). Identification and design principles of low hole effective mass p-type transparent conducting oxides. Nature Communications, 4, 2292. doi:10.1038/ncomms3292
Depending on the value of output, we have either the full 3x3 effective mass tensor, its 3 eigenvalues or an average
- Parameters:
output (str) – ‘eigs’ for eigenvalues, ‘tensor’ for the full
average (tensor and 'average' for an) –
doping_levels (bool) – True for the results to be given at
levels (different doping) –
results (False for) –
potentials (at different electron chemical) –
- Returns:
{temp:[]},’n’:{temp:[]}} with an array of effective mass tensor, eigenvalues of average value (depending on output) for each temperature and for each doping level. The ‘p’ links to hole effective mass tensor and ‘n’ to electron effective mass tensor.
- Return type:
If doping_levels=True,a dictionary {‘p’
- get_carrier_concentration()[source]
Gives the carrier concentration (in cm^-3).
- Returns:
[]} with an array of carrier concentration (in cm^-3) at each temperature The array relates to each step of electron chemical potential
- Return type:
a dictionary {temp
- get_complete_dos(structure: Structure, analyzer_for_second_spin=None)[source]
Gives a CompleteDos object with the DOS from the interpolated projected band structure.
- Parameters:
structure – necessary to identify sites for projection
analyzer_for_second_spin – must be specified to have a CompleteDos with both Spin components
- Returns:
from the interpolated projected band structure
- Return type:
Example of use in case of spin polarized case:
BoltztrapRunner(bs=bs,nelec=10,run_type=”DOS”,spin=1).run(path_dir=’dos_up/’) an_up=BoltztrapAnalyzer.from_files(“dos_up/boltztrap/”,dos_spin=1)
BoltztrapRunner(bs=bs,nelec=10,run_type=”DOS”,spin=-1).run(path_dir=’dos_dw/’) an_dw=BoltztrapAnalyzer.from_files(“dos_dw/boltztrap/”,dos_spin=-1)
cdos=an_up.get_complete_dos(bs.structure,an_dw)
- get_complexity_factor(output='average', temp=300, doping_levels=False, Lambda=0.5)[source]
Fermi surface complexity factor respect to calculated as explained in Ref. Gibbs, Z. M. et al., Effective mass and fermi surface complexity factor from ab initio band structure calculations. npj Computational Materials 3, 8 (2017).
- Parameters:
output – ‘average’ returns the complexity factor calculated using the average of the three diagonal components of the seebeck and conductivity tensors. ‘tensor’ returns the complexity factor respect to the three diagonal components of seebeck and conductivity tensors.
doping_levels – False means that the complexity factor is calculated for every value of the chemical potential True means that the complexity factor is calculated for every value of the doping levels for both n and p types
temp – temperature of calculated seebeck and conductivity.
Lambda – fitting parameter used to model the scattering (0.5 means constant relaxation time).
- Returns:
a list of values for the complexity factor w.r.t the chemical potential, if doping_levels is set at False; a dict with n an p keys that contain a list of values for the complexity factor w.r.t the doping levels, if doping_levels is set at True; if ‘tensor’ is selected, each element of the lists is a list containing the three components of the complexity factor.
- get_conductivity(output='eigs', doping_levels=True, relaxation_time=1e-14)[source]
Gives the conductivity (1/Ohm*m) in either a full 3x3 tensor form, as 3 eigenvalues, or as the average value (trace/3.0) If doping_levels=True, the results are given at different p and n doping levels (given by self.doping), otherwise it is given as a series of electron chemical potential values.
- Parameters:
output (str) – the type of output. ‘tensor’ give the full
tensor (3x3) –
and ('eigs' its 3 eigenvalues) –
eigenvalues ('average' the average of the three) –
doping_levels (bool) – True for the results to be given at
levels (different doping) –
results (False for) –
potentials (at different electron chemical) –
relaxation_time (float) – constant relaxation time in secs
- Returns:
{‘p’:[],’n’:[]}}. The ‘p’ links to conductivity at p-type doping and ‘n’ to the conductivity at n-type doping. Otherwise, returns a {temp:[]} dictionary. The result contains either the sorted three eigenvalues of the symmetric conductivity tensor (format=’eigs’) or a full tensor (3x3 array) (output=’tensor’) or as an average (output=’average’). The result includes a given constant relaxation time
units are 1/Ohm*m
- Return type:
If doping_levels=True, a dictionary {temp
- get_extreme(target_prop, maximize=True, min_temp=None, max_temp=None, min_doping=None, max_doping=None, isotropy_tolerance=0.05, use_average=True)[source]
This method takes in eigenvalues over a range of carriers, temperatures, and doping levels, and tells you what is the “best” value that can be achieved for the given target_property. Note that this method searches the doping dict only, not the full mu dict.
- Parameters:
target_prop – target property, i.e. “seebeck”, “power factor”, “conductivity”, “kappa”, or “zt”
maximize – True to maximize, False to minimize (e.g. kappa)
min_temp – minimum temperature allowed
max_temp – maximum temperature allowed
min_doping – minimum doping allowed (e.g., 1E18)
max_doping – maximum doping allowed (e.g., 1E20)
isotropy_tolerance – tolerance for isotropic (0.05 = 5%)
use_average – True for avg of eigenval, False for max eigenval
- Returns:
{“value”, “temperature”, “doping”, “isotropic”}
- Return type:
A dictionary with keys {“p”, “n”, “best”} with sub-keys
- get_hall_carrier_concentration()[source]
Gives the Hall carrier concentration (in cm^-3). This is the trace of the Hall tensor (see Boltztrap source code) Hall carrier concentration are not always exactly the same than carrier concentration.
- Returns:
[]} with an array of Hall carrier concentration (in cm^-3) at each temperature The array relates to each step of electron chemical potential
- Return type:
a dictionary {temp
- get_mu_bounds(temp=300)[source]
- Parameters:
temp – Temperature.
- Returns:
The chemical potential bounds at that temperature.
- get_power_factor(output='eigs', doping_levels=True, relaxation_time=1e-14)[source]
Gives the power factor (Seebeck^2 * conductivity) in units microW/(m*K^2) in either a full 3x3 tensor form, as 3 eigenvalues, or as the average value (trace/3.0) If doping_levels=True, the results are given at different p and n doping levels (given by self.doping), otherwise it is given as a series of electron chemical potential values.
- Parameters:
output (str) – the type of output. ‘tensor’ give the full 3x3
tensor –
and ('eigs' its 3 eigenvalues) –
eigenvalues ('average' the average of the three) –
doping_levels (bool) – True for the results to be given at
levels (different doping) –
results (False for) –
potentials (at different electron chemical) –
relaxation_time (float) – constant relaxation time in secs
- Returns:
{‘p’:[],’n’:[]}}. The ‘p’ links to power factor at p-type doping and ‘n’ to the conductivity at n-type doping. Otherwise, returns a {temp:[]} dictionary. The result contains either the sorted three eigenvalues of the symmetric power factor tensor (format=’eigs’) or a full tensor (3x3 array) ( output=’tensor’) or as an average (output=’average’). The result includes a given constant relaxation time
units are microW/(m K^2)
- Return type:
If doping_levels=True, a dictionary {temp
- get_seebeck(output='eigs', doping_levels=True)[source]
Gives the seebeck coefficient (microV/K) in either a full 3x3 tensor form, as 3 eigenvalues, or as the average value (trace/3.0) If doping_levels=True, the results are given at different p and n doping levels (given by self.doping), otherwise it is given as a series of electron chemical potential values.
- Parameters:
output (str) – the type of output. ‘tensor’ give the full
tensor (3x3) –
and ('eigs' its 3 eigenvalues) –
eigenvalues ('average' the average of the three) –
doping_levels (bool) – True for the results to be given at
levels (different doping) –
results (False for) –
potentials (at different electron chemical) –
- Returns:
{‘p’:[],’n’:[]}}. The ‘p’ links to Seebeck at p-type doping and ‘n’ to the Seebeck at n-type doping. Otherwise, returns a {temp:[]} dictionary The result contains either the sorted three eigenvalues of the symmetric Seebeck tensor (output=’eigs’) or a full tensor (3x3 array) ( output=’tensor’) or as an average (output=’average’).
units are microV/K
- Return type:
If doping_levels=True, a dictionary {temp
- get_seebeck_eff_mass(output='average', temp=300, doping_levels=False, Lambda=0.5)[source]
Seebeck effective mass calculated as explained in Ref. Gibbs, Z. M. et al., Effective mass and fermi surface complexity factor from ab initio band structure calculations. npj Computational Materials 3, 8 (2017).
- Parameters:
output – ‘average’ returns the seebeck effective mass calculated using the average of the three diagonal components of the seebeck tensor. ‘tensor’ returns the seebeck effective mass respect to the three diagonal components of the seebeck tensor.
doping_levels – False means that the seebeck effective mass is calculated for every value of the chemical potential True means that the seebeck effective mass is calculated for every value of the doping levels for both n and p types
temp – temperature of calculated seebeck.
Lambda – fitting parameter used to model the scattering (0.5 means constant relaxation time).
- Returns:
a list of values for the seebeck effective mass w.r.t the chemical potential, if doping_levels is set at False; a dict with n an p keys that contain a list of values for the seebeck effective mass w.r.t the doping levels, if doping_levels is set at True; if ‘tensor’ is selected, each element of the lists is a list containing the three components of the seebeck effective mass.
- get_symm_bands(structure: Structure, efermi, kpt_line=None, labels_dict=None)[source]
Function useful to read bands from Boltztrap output and get a BandStructureSymmLine object comparable with that one from a DFT calculation (if the same kpt_line is provided). Default kpt_line and labels_dict is the standard path of high symmetry k-point for the specified structure. They could be extracted from the BandStructureSymmLine object that you want to compare with. efermi variable must be specified to create the BandStructureSymmLine object (usually it comes from DFT or Boltztrap calc).
- get_thermal_conductivity(output='eigs', doping_levels=True, k_el=True, relaxation_time=1e-14)[source]
Gives the electronic part of the thermal conductivity in either a full 3x3 tensor form, as 3 eigenvalues, or as the average value (trace/3.0) If doping_levels=True, the results are given at different p and n doping levels (given by self.doping), otherwise it is given as a series of electron chemical potential values.
- Parameters:
output (str) – the type of output. ‘tensor’ give the full 3x3
tensor –
and ('eigs' its 3 eigenvalues) –
eigenvalues ('average' the average of the three) –
doping_levels (bool) – True for the results to be given at
levels (different doping) –
results (False for) –
potentials (at different electron chemical) –
k_el (bool) – True for k_0-PF*T, False for k_0
relaxation_time (float) – constant relaxation time in secs
- Returns:
{‘p’:[],’n’:[]}}. The ‘p’ links to thermal conductivity at p-type doping and ‘n’ to the thermal conductivity at n-type doping. Otherwise, returns a {temp:[]} dictionary. The result contains either the sorted three eigenvalues of the symmetric conductivity tensor (format=’eigs’) or a full tensor (3x3 array) ( output=’tensor’) or as an average (output=’average’). The result includes a given constant relaxation time
units are W/mK
- Return type:
If doping_levels=True, a dictionary {temp
- get_zt(output='eigs', doping_levels=True, relaxation_time=1e-14, k_l=1)[source]
Gives the ZT coefficient (S^2*cond*T/thermal cond) in either a full 3x3 tensor form, as 3 eigenvalues, or as the average value (trace/3.0) If doping_levels=True, the results are given at different p and n doping levels (given by self.doping), otherwise it is given as a series of electron chemical potential values. We assume a constant relaxation time and a constant lattice thermal conductivity.
- Parameters:
output (str) – the type of output. ‘tensor’ give the full 3x3
tensor –
and ('eigs' its 3 eigenvalues) –
eigenvalues ('average' the average of the three) –
doping_levels (bool) – True for the results to be given at
levels (different doping) –
results (False for) –
potentials (at different electron chemical) –
relaxation_time (float) – constant relaxation time in secs
k_l (float) – lattice thermal cond in W/(m*K)
- Returns:
{‘p’:[],’n’:[]}}. The ‘p’ links to ZT at p-type doping and ‘n’ to the ZT at n-type doping. Otherwise, returns a {temp:[]} dictionary. The result contains either the sorted three eigenvalues of the symmetric ZT tensor (format=’eigs’) or a full tensor (3x3 array) ( output=’tensor’) or as an average (output=’average’). The result includes a given constant relaxation time and lattice thermal conductivity
- Return type:
If doping_levels=True, a dictionary {temp
- static parse_cond_and_hall(path_dir, doping_levels=None)[source]
Parses the conductivity and Hall tensors.
- Parameters:
path_dir – Path containing .condtens / .halltens files
doping_levels – ([float]) - doping lvls, parse outtrans to get this.
- Returns:
mu_steps, cond, seebeck, kappa, hall, pn_doping_levels, mu_doping, seebeck_doping, cond_doping, kappa_doping, hall_doping, carrier_conc
- static parse_intrans(path_dir)[source]
Parses boltztrap.intrans mainly to extract the value of scissor applied to the bands or some other inputs.
- Parameters:
path_dir – (str) dir containing the boltztrap.intrans file
- Returns:
- a dictionary containing various inputs that had
been used in the Boltztrap run.
- Return type:
intrans (dict)
- static parse_outputtrans(path_dir)[source]
Parses .outputtrans file.
- Parameters:
path_dir – dir containing boltztrap.outputtrans
- Returns:
tuple - (run_type, warning, efermi, gap, doping_levels)
- static parse_struct(path_dir)[source]
Parses boltztrap.struct file (only the volume).
- Parameters:
path_dir – (str) dir containing the boltztrap.struct file
- Returns:
(float) volume
- static parse_transdos(path_dir, efermi, dos_spin=1, trim_dos=False)[source]
Parses .transdos (total DOS) and .transdos_x_y (partial DOS) files.
- Parameters:
path_dir – (str) dir containing DOS files
efermi – (float) Fermi energy
dos_spin – (int) -1 for spin down, +1 for spin up
trim_dos – (bool) whether to post-process / trim DOS.
- Returns:
tuple - (DOS, dict of partial DOS)
- exception BoltztrapError[source]
Bases:
Exception
Exception class for boltztrap. Raised when the boltztrap gives an error.
- class BoltztrapRunner(bs, nelec, dos_type='HISTO', energy_grid=0.005, lpfac=10, run_type='BOLTZ', band_nb=None, tauref=0, tauexp=0, tauen=0, soc=False, doping=None, energy_span_around_fermi=1.5, scissor=0.0, kpt_line=None, spin=None, cond_band=False, tmax=1300, tgrid=50, symprec=0.001, cb_cut=10, timeout=7200)[source]
Bases:
MSONable
This class is used to run Boltztrap on a band structure object.
- Parameters:
bs – A band structure object
nelec – the number of electrons
dos_type – two options for the band structure integration: “HISTO” (histogram) or “TETRA” using the tetrahedon method. TETRA typically gives better results (especially for DOSes) but takes more time
energy_grid – the energy steps used for the integration (eV)
lpfac – the number of interpolation points in the real space. By default 10 gives 10 time more points in the real space than the number of kpoints given in reciprocal space
run_type – type of boltztrap usage. by default - BOLTZ: (default) compute transport coefficients - BANDS: interpolate all bands contained in the energy range specified in energy_span_around_fermi variable, along specified k-points - DOS: compute total and partial dos (custom BoltzTraP code needed!) - FERMI: compute fermi surface or more correctly to get certain bands interpolated
band_nb – indicates a band number. Used for Fermi Surface interpolation (run_type=”FERMI”)
spin – specific spin component (1: up, -1: down) of the band selected in FERMI mode (mandatory).
cond_band – if a conduction band is specified in FERMI mode, set this variable as True
tauref – reference relaxation time. Only set to a value different than zero if we want to model beyond the constant relaxation time.
tauexp – exponent for the energy in the non-constant relaxation time approach
tauen – reference energy for the non-constant relaxation time approach
soc – results from spin-orbit coupling (soc) computations give typically non-polarized (no spin up or down) results but single electron occupations. If the band structure comes from a soc computation, you should set soc to True (default False)
doping – the fixed doping levels you want to compute. Boltztrap provides both transport values depending on electron chemical potential (fermi energy) and for a series of fixed carrier concentrations. By default, this is set to 1e16 to 1e22 in increments of factors of 10.
energy_span_around_fermi – usually the interpolation is not needed on the entire energy range but on a specific range around the Fermi level. This energy gives this range in eV. by default it is 1.5 eV. If DOS or BANDS type are selected, this range is automatically set to cover the entire energy range.
scissor – scissor to apply to the band gap (eV). This applies a scissor operation moving the band edges without changing the band shape. This is useful to correct the often underestimated band gap in DFT. Default is 0.0 (no scissor)
kpt_line – list of fractional coordinates of kpoints as arrays or list of Kpoint objects for BANDS mode calculation (standard path of high symmetry k-points is automatically set as default)
tmax – Maximum temperature (K) for calculation (default=1300)
tgrid – Temperature interval for calculation (default=50)
symprec – 1e-3 is the default in pymatgen. If the kmesh has been generated using a different symprec, it has to be specified to avoid a “factorization error” in BoltzTraP calculation. If a kmesh that spans the whole Brillouin zone has been used, or to disable all the symmetries, set symprec to None.
cb_cut – by default 10% of the highest conduction bands are removed because they are often not accurate. Tune cb_cut to change the percentage (0-100) of bands that are removed.
timeout – overall time limit (in seconds): mainly to avoid infinite loop when trying to find Fermi levels.
- run(path_dir=None, convergence=True, write_input=True, clear_dir=False, max_lpfac=150, min_egrid=5e-05)[source]
Write inputs (optional), run BoltzTraP, and ensure convergence (optional).
- Parameters:
path_dir (str) – directory in which to run BoltzTraP
convergence (bool) – whether to check convergence and make corrections if needed
write_input – (bool) whether to write input files before the run (required for convergence mode)
clear_dir – (bool) whether to remove all files in the path_dir before starting
max_lpfac – (float) maximum lpfac value to try before reducing egrid in convergence mode
min_egrid – (float) minimum egrid value to try before giving up in convergence mode
- write_def(output_file) None [source]
Writes the def to an output file.
- Parameters:
output_file – Filename
- write_energy(output_file) None [source]
Writes the energy to an output file.
- Parameters:
output_file – Filename
- write_input(output_dir) None [source]
Writes the input files.
- Parameters:
output_dir – Directory to write the input files.
- write_intrans(output_file) None [source]
Writes the intrans to an output file.
- Parameters:
output_file – Filename
- compare_sym_bands(bands_obj, bands_ref_obj, nb=None)[source]
Compute the mean of correlation between bzt and vasp bandstructure on sym line, for all bands and locally (for each branches) the difference squared (%) if nb is specified.
- eta_from_seebeck(seeb, Lambda)[source]
It takes a value of seebeck and adjusts the analytic seebeck until it’s equal.
- Returns:
eta where the two seebeck coefficients are equal (reduced chemical potential).
- Return type:
float
- seebeck_eff_mass_from_carr(eta, n, T, Lambda)[source]
Calculate seebeck effective mass at a certain carrier concentration eta in kB*T units, n in cm-3, T in K, returns mass in m0 units.
pymatgen.electronic_structure.boltztrap2 module
pymatgen.electronic_structure.cohp module
This module defines classes to represent crystal orbital Hamilton populations (COHP) and integrated COHP (ICOHP), but can also be used for crystal orbital overlap populations (COOP) or crystal orbital bond indices (COBIs). If you use this module, please cite: J. George, G. Petretto, A. Naik, M. Esters, A. J. Jackson, R. Nelson, R. Dronskowski, G.-M. Rignanese, G. Hautier, “Automated Bonding Analysis with Crystal Orbital Hamilton Populations”, ChemPlusChem 2022, e202200123, DOI: 10.1002/cplu.202200123.
- class Cohp(efermi, energies, cohp, are_coops=False, are_cobis=False, are_multi_center_cobis=False, icohp=None)[source]
Bases:
MSONable
Basic COHP object.
- Parameters:
are_coops – Indicates whether this object describes COOPs.
are_cobis – Indicates whether this object describes COBIs.
are_multi_center_cobis – Indicates whether this object describes multi-center COBIs
efermi – Fermi energy.
energies – A sequence of energies.
({Spin (icohp) – np.array}): representing the COHP for each spin.
({Spin – np.array}): representing the ICOHP for each spin.
- classmethod from_dict(dct: dict[str, Any]) Cohp [source]
Returns a COHP object from a dict representation of the COHP.
- get_cohp(spin=None, integrated=False)[source]
Returns the COHP or ICOHP for a particular spin.
- Parameters:
spin – Spin. Can be parsed as spin object, integer (-1/1) or str (“up”/”down”)
integrated – Return COHP (False) or ICOHP (True)
- Returns:
Returns the CHOP or ICOHP for the input spin. If Spin is None and both spins are present, both spins will be returned as a dictionary.
- class CompleteCohp(structure, avg_cohp, cohp_dict, bonds=None, are_coops=False, are_cobis=False, are_multi_center_cobis=False, orb_res_cohp=None)[source]
Bases:
Cohp
A wrapper class that defines an average COHP, and individual COHPs.
- all_cohps[source]
A dict of COHPs for individual bonds of the form {label: COHP}.
- Type:
dict[str, Sequence[float]]
- Parameters:
structure – Structure associated with this COHP.
avg_cohp – The average cohp as a COHP object.
cohp_dict – A dict of COHP objects for individual bonds of the form {label: COHP}
bonds – A dict containing information on the bonds of the form {label: {key: val}}. The key-val pair can be any information the user wants to put in, but typically contains the sites, the bond length, and the number of bonds. If nothing is supplied, it will default to an empty dict.
are_coops – indicates whether the Cohp objects are COOPs. Defaults to False for COHPs.
are_cobis – indicates whether the Cohp objects are COBIs. Defaults to False for COHPs.
are_multi_center_cobis – indicates whether the Cohp objects are multi-center COBIs. Defaults to False for COHPs.
orb_res_cohp – Orbital-resolved COHPs.
- classmethod from_dict(dct: dict) Self [source]
Returns CompleteCohp object from dict representation.
- classmethod from_file(fmt, filename=None, structure_file=None, are_coops=False, are_cobis=False, are_multi_center_cobis=False)[source]
Creates a CompleteCohp object from an output file of a COHP calculation. Valid formats are either LMTO (for the Stuttgart LMTO-ASA code) or LOBSTER (for the LOBSTER code).
- Parameters:
fmt – A string for the code that was used to calculate the COHPs so that the output file can be handled correctly. Can take the values “LMTO” or “LOBSTER”.
filename – Name of the COHP output file. Defaults to COPL for LMTO and COHPCAR.lobster/COOPCAR.lobster for LOBSTER.
structure_file – Name of the file containing the structure. If no file name is given, use CTRL for LMTO and POSCAR for LOBSTER.
are_coops – Indicates whether the populations are COOPs or COHPs. Defaults to False for COHPs.
are_cobis – Indicates whether the populations are COBIs or COHPs. Defaults to False for COHPs.
are_multi_center_cobis – Indicates whether this file includes information on multi-center COBIs
- Returns:
A CompleteCohp object.
- get_cohp_by_label(label, summed_spin_channels=False)[source]
Get specific COHP object.
- Parameters:
label – string (for newer Lobster versions: a number)
summed_spin_channels – bool, will sum the spin channels and return the sum in Spin.up if true
- Returns:
Returns the COHP object to simplify plotting
- get_orbital_resolved_cohp(label, orbitals, summed_spin_channels=False)[source]
Get orbital-resolved COHP.
- Parameters:
label – bond label (Lobster: labels as in ICOHPLIST/ICOOPLIST.lobster).
orbitals – The orbitals as a label, or list or tuple of the form [(n1, orbital1), (n2, orbital2)]. Orbitals can either be str, int, or Orbital.
summed_spin_channels – bool, will sum the spin channels and return the sum in Spin.up if true
- Returns:
A Cohp object if CompleteCohp contains orbital-resolved cohp, or None if it doesn’t.
- Note: It currently assumes that orbitals are str if they aren’t the
other valid types. This is not ideal, but the easiest way to avoid unicode issues between python 2 and python 3.
- get_summed_cohp_by_label_and_orbital_list(label_list, orbital_list, divisor=1, summed_spin_channels=False)[source]
Returns a COHP object that includes a summed COHP divided by divisor.
- Parameters:
label_list – list of labels for the COHP that should be included in the summed cohp
orbital_list – list of orbitals for the COHPs that should be included in the summed cohp (same order as label_list)
divisor – float/int, the summed cohp will be divided by this divisor
summed_spin_channels – bool, will sum the spin channels and return the sum in Spin.up if true
- Returns:
Returns a COHP object including a summed COHP
- get_summed_cohp_by_label_list(label_list, divisor=1, summed_spin_channels=False)[source]
Returns a COHP object that includes a summed COHP divided by divisor.
- Parameters:
label_list – list of labels for the COHP that should be included in the summed cohp
divisor – float/int, the summed cohp will be divided by this divisor
summed_spin_channels – bool, will sum the spin channels and return the sum in Spin.up if true
- Returns:
Returns a COHP object including a summed COHP
- class IcohpCollection(list_labels, list_atom1, list_atom2, list_length, list_translation, list_num, list_icohp, is_spin_polarized, list_orb_icohp=None, are_coops=False, are_cobis=False)[source]
Bases:
MSONable
Class to store IcohpValues.
- is_spin_polarized[source]
Boolean to indicate if the Lobster calculation was done spin polarized or not.
- Type:
bool
- Parameters:
list_labels – list of labels for ICOHP/ICOOP values
list_atom1 – list of str of atomnames e.g. “O1”
list_atom2 – list of str of atomnames e.g. “O1”
list_length – list of lengths of corresponding bonds in Angstrom
list_translation – list of translation list, e.g. [0,0,0]
list_num – list of equivalent bonds, usually 1 starting from Lobster 3.0.0
list_icohp – list of dict={Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}
is_spin_polarized – Boolean to indicate if the Lobster calculation was done spin polarized or not Boolean to indicate if the Lobster calculation was done spin polarized or not
list_orb_icohp – list of dict={[str(Orbital1)-str(Orbital2)]: {“icohp”:{Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}, “orbitals”:[Orbital1, Orbital2]}}
are_coops – Boolean to indicate whether ICOOPs are stored
are_cobis – Boolean to indicate whether ICOBIs are stored.
- extremum_icohpvalue(summed_spin_channels=True, spin=Spin.up)[source]
Get ICOHP/ICOOP of strongest bond.
- Parameters:
summed_spin_channels – Boolean to indicate whether the ICOHPs/ICOOPs of both spin channels should be summed.
spin – if summed_spin_channels is equal to False, this spin indicates which spin channel should be returned
- Returns:
lowest ICOHP/largest ICOOP value (i.e. ICOHP/ICOOP value of strongest bond)
- get_icohp_by_label(label, summed_spin_channels=True, spin=Spin.up, orbitals=None)[source]
Get an icohp value for a certain bond as indicated by the label (bond labels starting by “1” as in ICOHPLIST/ICOOPLIST).
- Parameters:
label – label in str format (usually the bond number in Icohplist.lobster/Icooplist.lobster
summed_spin_channels – Boolean to indicate whether the ICOHPs/ICOOPs of both spin channels should be summed
spin – if summed_spin_channels is equal to False, this spin indicates which spin channel should be returned
orbitals – List of Orbital or “str(Orbital1)-str(Orbital2)”
- Returns:
float describing ICOHP/ICOOP value
- get_icohp_dict_by_bondlengths(minbondlength=0.0, maxbondlength=8.0)[source]
Get a dict of IcohpValues corresponding to certain bond lengths.
- Parameters:
minbondlength – defines the minimum of the bond lengths of the bonds
maxbondlength – defines the maximum of the bond lengths of the bonds.
- Returns:
dict of IcohpValues, the keys correspond to the values from the initial list_labels.
- get_icohp_dict_of_site(site, minsummedicohp=None, maxsummedicohp=None, minbondlength=0.0, maxbondlength=8.0, only_bonds_to=None)[source]
Get a dict of IcohpValue for a certain site (indicated by integer).
- Parameters:
site – integer describing the site of interest, order as in Icohplist.lobster/Icooplist.lobster, starts at 0
minsummedicohp – float, minimal icohp/icoop of the bonds that are considered. It is the summed ICOHP value from both spin channels for spin polarized cases
maxsummedicohp – float, maximal icohp/icoop of the bonds that are considered. It is the summed ICOHP value from both spin channels for spin polarized cases
minbondlength – float, defines the minimum of the bond lengths of the bonds
maxbondlength – float, defines the maximum of the bond lengths of the bonds
only_bonds_to – list of strings describing the bonding partners that are allowed, e.g. [‘O’]
- Returns:
dict of IcohpValues, the keys correspond to the values from the initial list_labels
- get_summed_icohp_by_label_list(label_list, divisor=1.0, summed_spin_channels=True, spin=Spin.up)[source]
Get the sum of several ICOHP values that are indicated by a list of labels (labels of the bonds are the same as in ICOHPLIST/ICOOPLIST).
- Parameters:
label_list – list of labels of the ICOHPs/ICOOPs that should be summed
divisor – is used to divide the sum
summed_spin_channels – Boolean to indicate whether the ICOHPs/ICOOPs of both spin channels should be summed
spin – if summed_spin_channels is equal to False, this spin indicates which spin channel should be returned
- Returns:
float that is a sum of all ICOHPs/ICOOPs as indicated with label_list
- class IcohpValue(label, atom1, atom2, length, translation, num, icohp, are_coops=False, are_cobis=False, orbitals=None)[source]
Bases:
MSONable
Class to store information on an ICOHP or ICOOP value.
- icohp[source]
A dictionary of the ICOHP/COHP values. The keys are Spin.up and Spin.down.
- Type:
dict
- num_bonds[source]
The number of bonds used for the average COHP (relevant for Lobster versions <3.0).
- Type:
int
- Parameters:
label – label for the icohp
atom1 – str of atom that is contributing to the bond
atom2 – str of second atom that is contributing to the bond
length – float of bond lengths
translation – translation list, e.g. [0,0,0]
num – integer describing how often the bond exists
icohp – dict={Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}
are_coops – if True, this are COOPs
are_cobis – if True, this are COBIs
orbitals – {[str(Orbital1)-str(Orbital2)]: {“icohp”:{Spin.up: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}, “orbitals”:[Orbital1, Orbital2]}}.
- property icohp[source]
Dict with icohps for spinup and spindown :returns: icohpvalue for spin.up, Spin.down: icohpvalue for spin.down}. :rtype: dict={Spin.up
- icohpvalue(spin=Spin.up)[source]
- Parameters:
spin – Spin.up or Spin.down.
- Returns:
icohpvalue (float) corresponding to chosen spin.
- icohpvalue_orbital(orbitals, spin=Spin.up)[source]
- Parameters:
orbitals – List of Orbitals or “str(Orbital1)-str(Orbital2)”
spin – Spin.up or Spin.down.
- Returns:
icohpvalue (float) corresponding to chosen spin.
- property is_spin_polarized: bool[source]
Tells if spin polarized calculation or not.
- Returns:
Boolean.
- property num_bonds[source]
Tells the number of bonds for which the ICOHP value is an average.
- Returns:
Int.
- get_integrated_cohp_in_energy_range(cohp, label, orbital=None, energy_range=None, relative_E_Fermi=True, summed_spin_channels=True)[source]
Method that can integrate completecohp objects which include data on integrated COHPs :param cohp: CompleteCOHP object :param label: label of the COHP data :param orbital: If not None, a orbital resolved integrated COHP will be returned :param energy_range: if None, returns icohp value at Fermi level;
if float, integrates from this float up to the Fermi level; if [float,float], will integrate in between
- Parameters:
relative_E_Fermi – if True, energy scale with E_Fermi at 0 eV is chosen
summed_spin_channels – if True, Spin channels will be summed.
- Returns:
float indicating the integrated COHP if summed_spin_channels==True, otherwise dict of the following form { Spin.up:float, Spin.down:float}
pymatgen.electronic_structure.core module
This module provides core classes needed by all define electronic structure, such as the Spin, Orbital, etc.
- class Magmom(moment: float | Sequence[float] | np.ndarray | Magmom, saxis: Sequence[float] = (0, 0, 1))[source]
Bases:
MSONable
New class in active development. Use with caution, feedback is appreciated.
Class to handle magnetic moments. Defines the magnetic moment of a site or species relative to a spin quantization axis. Designed for use in electronic structure calculations.
For the general case, Magmom can be specified by a vector, e.g. m = Magmom([1.0, 1.0, 2.0]), and subscripts will work as expected, e.g. m[0] gives 1.0
For collinear calculations, Magmom can assumed to be scalar-like, e.g. m = Magmom(5.0) will work as expected, e.g. float(m) gives 5.0
Both of these cases should be safe and shouldn’t give any surprises, but more advanced functionality is available if required.
There also exist useful static methods for lists of magmoms:
Magmom.are_collinear(magmoms) - if true, a collinear electronic structure calculation can be safely initialized, with float(Magmom) giving the expected scalar magnetic moment value
Magmom.get_consistent_set_and_saxis(magmoms) - for non-collinear electronic structure calculations, a global, consistent spin axis has to be used. This method returns a list of Magmoms which all share a common spin axis, along with the global spin axis.
All methods that take lists of magmoms will accept magmoms either as Magmom objects or as scalars/lists and will automatically convert to a Magmom representation internally.
The following methods are also particularly useful in the context of VASP calculations:
Magmom.get_xyz_magmom_with_001_saxis()
Magmom.get_00t_magmom_with_xyz_saxis()
See VASP documentation for more information:
https://cms.mpi.univie.ac.at/wiki/index.php/SAXIS
- Parameters:
moment – magnetic moment, supplied as float or list/np.ndarray
saxis – spin axis, supplied as list/np.ndarray, parameter will be converted to unit vector (default is [0, 0, 1]).
- Returns:
Magmom object
- static are_collinear(magmoms) bool [source]
Method checks to see if a set of magnetic moments are collinear with each other.
- Parameters:
magmoms – list of magmoms (Magmoms, scalars or vectors).
- Returns:
bool.
- classmethod from_global_moment_and_saxis(global_moment, saxis) Self [source]
Convenience method to initialize Magmom from a given global magnetic moment, i.e. magnetic moment with saxis=(0,0,1), and provided saxis.
Method is useful if you do not know the components of your magnetic moment in frame of your desired saxis.
- Parameters:
global_moment – global magnetic moment
saxis – desired saxis
- classmethod from_moment_relative_to_crystal_axes(moment, lattice)[source]
Obtaining a Magmom object from a magnetic moment provided relative to crystal axes.
Used for obtaining moments from magCIF file.
- Parameters:
moment – list of floats specifying vector magmom
lattice – Lattice
- Returns:
Magmom
- get_00t_magmom_with_xyz_saxis()[source]
For internal implementation reasons, in non-collinear calculations VASP prefers the following.
MAGMOM = 0 0 total_magnetic_moment SAXIS = x y z
to an equivalent:
MAGMOM = x y z SAXIS = 0 0 1
This method returns a Magmom object with magnetic moment [0, 0, t], where t is the total magnetic moment, and saxis rotated as required.
A consistent direction of saxis is applied such that t might be positive or negative depending on the direction of the initial moment. This is useful in the case of collinear structures, rather than constraining assuming t is always positive.
- Returns:
Magmom
- static get_consistent_set_and_saxis(magmoms, saxis=None)[source]
Method to ensure a list of magmoms use the same spin axis. Returns a tuple of a list of Magmoms and their global spin axis.
- Parameters:
magmoms – list of magmoms (Magmoms, scalars or vectors)
saxis – can provide a specific global spin axis
- Returns:
(list of Magmoms, global spin axis) tuple
- get_moment(saxis=(0, 0, 1))[source]
Get magnetic moment relative to a given spin quantization axis. If no axis is provided, moment will be given relative to the Magmom’s internal spin quantization axis, i.e. equivalent to Magmom.moment.
- Parameters:
saxis – (list/numpy array) spin quantization axis
- Returns:
np.ndarray of length 3
- get_moment_relative_to_crystal_axes(lattice)[source]
If scalar magmoms, moments will be given arbitrarily along z. Used for writing moments to magCIF file.
- Parameters:
lattice – Lattice
- Returns:
vector as list of floats
- static get_suggested_saxis(magmoms)[source]
This method returns a suggested spin axis for a set of magmoms, taking the largest magnetic moment as the reference. For calculations with collinear spins, this would give a sensible saxis for a ncl calculation.
- Parameters:
magmoms – list of magmoms (Magmoms, scalars or vectors)
- Returns:
np.ndarray of length 3
- get_xyz_magmom_with_001_saxis()[source]
Returns a Magmom in the default setting of saxis = [0, 0, 1] and the magnetic moment rotated as required.
- Returns:
Magmom
- property global_moment[source]
Get the magnetic moment defined in an arbitrary global reference frame.
- Returns:
np.ndarray of length 3
- static have_consistent_saxis(magmoms) bool [source]
This method checks that all Magmom objects in a list have a consistent spin quantization axis. To write MAGMOM tags to a VASP INCAR, a global SAXIS value for all magmoms has to be used. If saxis are inconsistent, can create consistent set with: Magmom.get_consistent_set(magmoms).
- Parameters:
magmoms – list of magmoms (Magmoms, scalars or vectors)
- Returns:
bool
- class Orbital(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]
Bases:
Enum
Enum type for specific orbitals. The indices are the order in which the orbitals are reported in VASP and has no special meaning.
pymatgen.electronic_structure.dos module
This module defines classes to represent the density of states, etc.
- class CompleteDos(structure: Structure, total_dos: Dos, pdoss: Mapping[PeriodicSite, Mapping[Orbital, Mapping[Spin, ArrayLike]]], normalize: bool = False)[source]
Bases:
Dos
This wrapper class defines a total dos, and also provides a list of PDos. Mainly used by pymatgen.io.vasp.Vasprun to create a complete Dos from a vasprun.xml file. You are unlikely to try to generate this object manually.
- Parameters:
structure – Structure associated with this particular DOS.
total_dos – total Dos for structure
pdoss – The pdoss are supplied as an {Site: {Orbital: {Spin:Densities}}}
normalize – Whether to normalize the densities by the volume of the structure. If True, the units of the densities are states/eV/Angstrom^3. Otherwise, the units are states/eV.
- static fp_to_dict(fp: NamedTuple) dict [source]
Converts a fingerprint into a dictionary.
- Parameters:
fp – The DOS fingerprint to be converted into a dictionary
- Returns:
A dict of the fingerprint Keys=type, Values=np.ndarray(energies, densities)
- Return type:
dict
- classmethod from_dict(dct) CompleteDos [source]
Returns CompleteDos object from dict representation.
- get_band_center(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None, erange: list[float] | None = None) float [source]
Compute the orbital-projected band center, defined as the first moment relative to the Fermi level
int_{-inf}^{+inf} rho(E)*E dE/int_{-inf}^{+inf} rho(E) dE
based on the work of Hammer and Norskov, Surf. Sci., 343 (1995) where the limits of the integration can be modified by erange and E is the set of energies taken with respect to the Fermi level. Note that the band center is often highly sensitive to the selected erange.
- Parameters:
band – Orbital type to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
erange – [min, max] energy range to consider, with respect to the Fermi level. Default is None, which means all energies are considered.
- Returns:
band center in eV, often denoted epsilon_d for the d-band center
- Return type:
float
- get_band_filling(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None) float [source]
Compute the orbital-projected band filling, defined as the zeroth moment up to the Fermi level.
- Parameters:
band – Orbital type to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
- Returns:
band filling in eV, often denoted f_d for the d-band
- Return type:
float
- get_band_kurtosis(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None, erange: list[float] | None = None) float [source]
- Get the orbital-projected kurtosis, defined as the fourth standardized moment
int_{-inf}^{+inf} rho(E)*(E-E_center)^4 dE/int_{-inf}^{+inf} rho(E) dE) / (int_{-inf}^{+inf} rho(E)*(E-E_center)^2 dE/int_{-inf}^{+inf} rho(E) dE))^2
where E_center is the orbital-projected band center, the limits of the integration can be modified by erange, and E is the set of energies taken with respect to the Fermi level. Note that the skewness is often highly sensitive to the selected erange.
- Parameters:
band – Orbital type to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
erange – [min, max] energy range to consider, with respect to the Fermi level. Default is None, which means all energies are considered.
- Returns:
orbital-projected kurtosis (dimensionless)
- Return type:
float
- get_band_skewness(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None, erange: list[float] | None = None) float [source]
- Get the orbital-projected skewness, defined as the third standardized moment
int_{-inf}^{+inf} rho(E)*(E-E_center)^3 dE/int_{-inf}^{+inf} rho(E) dE) / (int_{-inf}^{+inf} rho(E)*(E-E_center)^2 dE/int_{-inf}^{+inf} rho(E) dE))^(3/2)
where E_center is the orbital-projected band center, the limits of the integration can be modified by erange, and E is the set of energies taken with respect to the Fermi level. Note that the skewness is often highly sensitive to the selected erange.
- Parameters:
band – Orbitals to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
erange – [min, max] energy range to consider, with respect to the Fermi level. Default is None, which means all energies are considered.
- Returns:
orbital-projected skewness (dimensionless)
- Return type:
float
- get_band_width(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None, erange: list[float] | None = None) float [source]
- Get the orbital-projected band width, defined as the square root of the second moment
sqrt(int_{-inf}^{+inf} rho(E)*(E-E_center)^2 dE/int_{-inf}^{+inf} rho(E) dE)
where E_center is the orbital-projected band center, the limits of the integration can be modified by erange, and E is the set of energies taken with respect to the Fermi level. Note that the band width is often highly sensitive to the selected erange.
- Parameters:
band – Orbital type to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
erange – [min, max] energy range to consider, with respect to the Fermi level. Default is None, which means all energies are considered.
- Returns:
Orbital-projected band width in eV
- Return type:
float
- get_dos_fp(type: str = 'summed_pdos', binning: bool = True, min_e: float | None = None, max_e: float | None = None, n_bins: int = 256, normalize: bool = True) NamedTuple [source]
Generates the DOS fingerprint.
Based on work of:
F. Knoop, T. A. r Purcell, M. Scheffler, C. Carbogno, J. Open Source Softw. 2020, 5, 2671. Source - https://gitlab.com/vibes-developers/vibes/-/tree/master/vibes/materials_fp Copyright (c) 2020 Florian Knoop, Thomas A.R.Purcell, Matthias Scheffler, Christian Carbogno.
- Parameters:
type (str) – Specify fingerprint type needed can accept ‘{s/p/d/f/}summed_{pdos/tdos}’
summed_pdos) ((default is) –
binning (bool) – If true, the DOS fingerprint is binned using np.linspace and n_bins. Default is True.
min_e (float) – The minimum mode energy to include in the fingerprint (default is None)
max_e (float) – The maximum mode energy to include in the fingerprint (default is None)
n_bins (int) – Number of bins to be used in the fingerprint (default is 256)
normalize (bool) – If true, normalizes the area under fp to equal to 1. Default is True.
- Raises:
ValueError – If type is not one of the accepted values {s/p/d/f/}summed_{pdos/tdos}.
- Returns:
- The electronic density of states fingerprint
of format (energies, densities, type, n_bins)
- Return type:
Fingerprint(namedtuple)
- static get_dos_fp_similarity(fp1: NamedTuple, fp2: NamedTuple, col: int = 1, pt: int | str = 'All', normalize: bool = False, tanimoto: bool = False) float [source]
Calculates the similarity index (dot product) of two fingerprints.
- Parameters:
fp1 (NamedTuple) – The 1st dos fingerprint object
fp2 (NamedTuple) – The 2nd dos fingerprint object
col (int) – The item in the fingerprints (0:energies,1: densities) to take the dot product of (default is 1)
pt (int or str) – The index of the point that the dot product is to be taken (default is All)
normalize (bool) – If True normalize the scalar product to 1 (default is False)
tanimoto (bool) – If True will compute Tanimoto index (default is False)
- Raises:
ValueError – If both tanimoto and normalize are set to True.
- Returns:
Similarity index given by the dot product
- Return type:
float
- get_element_dos() dict[SpeciesLike, Dos] [source]
Get element projected Dos.
- Returns:
dict[Element, Dos]
- get_element_spd_dos(el: SpeciesLike) dict[OrbitalType, Dos] [source]
Get element and spd projected Dos.
- Parameters:
el – Element in Structure.composition associated with CompleteDos
- Returns:
e.g. {OrbitalType.s: Dos object, …}
- Return type:
dict[OrbitalType, Dos]
- get_hilbert_transform(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None) Dos [source]
Return the Hilbert transform of the orbital-projected density of states, often plotted for a Newns-Anderson analysis.
- Parameters:
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
band – Orbitals to get the band center of (default is d-band)
- Returns:
Hilbert transformation of the projected DOS.
- get_n_moment(n: int, band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None, erange: list[float] | None = None, center: bool = True) float [source]
- Get the nth moment of the DOS centered around the orbital-projected band center, defined as
int_{-inf}^{+inf} rho(E)*(E-E_center)^n dE/int_{-inf}^{+inf} rho(E) dE
where n is the order, E_center is the orbital-projected band center, the limits of the integration can be modified by erange, and E is the set of energies taken with respect to the Fermi level. If center is False, then the E_center reference is not used.
- Parameters:
n – The order for the moment
band – Orbital type to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
erange – [min, max] energy range to consider, with respect to the Fermi level. Default is None, which means all energies are considered.
center – Take moments with respect to the band center
- Returns:
Orbital-projected nth moment in eV
- get_normalized() CompleteDos [source]
Returns a normalized version of the CompleteDos.
- get_site_dos(site: PeriodicSite) Dos [source]
Get the total Dos for a site (all orbitals).
- Parameters:
site – Site in Structure associated with CompleteDos.
- Returns:
Dos containing summed orbital densities for site.
- get_site_orbital_dos(site: PeriodicSite, orbital: Orbital) Dos [source]
Get the Dos for a particular orbital of a particular site.
- Parameters:
site – Site in Structure associated with CompleteDos.
orbital – Orbital in the site.
- Returns:
Dos containing densities for orbital of site.
- get_site_spd_dos(site: PeriodicSite) dict[OrbitalType, Dos] [source]
Get orbital projected Dos of a particular site.
- Parameters:
site – Site in Structure associated with CompleteDos.
- Returns:
Dos}, e.g. {OrbitalType.s: Dos object, …}
- Return type:
dict of {OrbitalType
- get_site_t2g_eg_resolved_dos(site: PeriodicSite) dict[str, Dos] [source]
Get the t2g, eg projected DOS for a particular site.
- Parameters:
site – Site in Structure associated with CompleteDos.
- Returns:
A dict {“e_g”: Dos, “t2g”: Dos} containing summed e_g and t2g DOS for the site.
- Return type:
dict[str, Dos]
- get_spd_dos() dict[OrbitalType, Dos] [source]
Get orbital projected Dos.
- Returns:
e.g. {OrbitalType.s: Dos object, …}
- Return type:
dict[OrbitalType, Dos]
- get_upper_band_edge(band: OrbitalType = OrbitalType.d, elements: list[SpeciesLike] | None = None, sites: list[PeriodicSite] | None = None, spin: Spin | None = None, erange: list[float] | None = None) float [source]
Get the orbital-projected upper band edge. The definition by Xin et al. Phys. Rev. B, 89, 115114 (2014) is used, which is the highest peak position of the Hilbert transform of the orbital-projected DOS.
- Parameters:
band – Orbital type to get the band center of (default is d-band)
elements – Elements to get the band center of (cannot be used in conjunction with site)
sites – Sites to get the band center of (cannot be used in conjunction with el)
spin – Spin channel to use. By default, the spin channels will be combined.
erange – [min, max] energy range to consider, with respect to the Fermi level. Default is None, which means all energies are considered.
- Returns:
Upper band edge in eV, often denoted epsilon_u
- property spin_polarization: float | None[source]
Calculates spin polarization at Fermi level. If the calculation is not spin-polarized, None will be returned.
See Sanvito et al., doi: 10.1126/sciadv.1602241 for an example usage.
- Returns:
- spin polarization in range [0, 1], will also return NaN if spin
polarization ill-defined (e.g. for insulator).
- Return type:
float
- class DOS(energies: ArrayLike, densities: ArrayLike, efermi: float)[source]
Bases:
Spectrum
Replacement basic DOS object. All other DOS objects are extended versions of this object. Work in progress.
- densities[source]
A dict of spin densities, e.g., {Spin.up: […], Spin.down: […]}.
- Type:
dict[Spin, Sequence[float]]
- Parameters:
energies – A sequence of energies
densities (ndarray) – Either a Nx1 or a Nx2 array. If former, it is interpreted as a Spin.up only density. Otherwise, the first column is interpreted as Spin.up and the other is Spin.down.
efermi – Fermi level energy.
- get_cbm_vbm(tol: float = 0.001, abs_tol: bool = False, spin=None)[source]
Expects a DOS object and finds the cbm and vbm.
- Parameters:
tol – tolerance in occupations for determining the gap
abs_tol – An absolute tolerance (True) and a relative one (False)
spin – Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel.
- Returns:
float in eV corresponding to the gap
- Return type:
(cbm, vbm)
- get_gap(tol: float = 0.001, abs_tol: bool = False, spin: Spin | None = None)[source]
Expects a DOS object and finds the gap.
- Parameters:
tol – tolerance in occupations for determining the gap
abs_tol – An absolute tolerance (True) and a relative one (False)
spin – Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel.
- Returns:
gap in eV
- get_interpolated_gap(tol: float = 0.001, abs_tol: bool = False, spin: Spin | None = None)[source]
Expects a DOS object and finds the gap.
- Parameters:
tol – tolerance in occupations for determining the gap
abs_tol – Set to True for an absolute tolerance and False for a relative one.
spin – Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel.
- Returns:
Tuple of floats in eV corresponding to the gap, cbm and vbm.
- Return type:
(gap, cbm, vbm)
- class Dos(efermi: float, energies: ArrayLike, densities: Mapping[Spin, ArrayLike], norm_vol: float | None = None)[source]
Bases:
MSONable
Basic DOS object. All other DOS objects are extended versions of this object.
- densities[source]
A dict of spin densities, e.g., {Spin.up: […], Spin.down: […]}.
- Type:
dict[Spin, Sequence[float]]
- Parameters:
efermi – Fermi level energy
energies – A sequences of energies
(dict[Spin (densities) – np.array]): representing the density of states for each Spin.
norm_vol – The volume used to normalize the densities. Defaults to 1 if None which will not perform any normalization. If not None, the resulting density will have units of states/eV/Angstrom^3, otherwise the density will be in states/eV.
- get_cbm_vbm(tol: float = 0.001, abs_tol: bool = False, spin: Spin | None = None)[source]
Expects a DOS object and finds the cbm and vbm.
- Parameters:
tol – tolerance in occupations for determining the gap
abs_tol – An absolute tolerance (True) and a relative one (False)
spin – Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel.
- Returns:
float in eV corresponding to the gap
- Return type:
(cbm, vbm)
- get_densities(spin: Spin | None = None)[source]
Returns the density of states for a particular spin.
- Parameters:
spin – Spin
- Returns:
Returns the density of states for a particular spin. If Spin is None, the sum of all spins is returned.
- get_gap(tol: float = 0.001, abs_tol: bool = False, spin: Spin | None = None)[source]
Expects a DOS object and finds the gap.
- Parameters:
tol – tolerance in occupations for determining the gap
abs_tol – An absolute tolerance (True) and a relative one (False)
spin – Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel.
- Returns:
gap in eV
- get_interpolated_gap(tol: float = 0.001, abs_tol: bool = False, spin: Spin | None = None)[source]
Expects a DOS object and finds the gap.
- Parameters:
tol – tolerance in occupations for determining the gap
abs_tol – Set to True for an absolute tolerance and False for a relative one.
spin – Possible values are None - finds the gap in the summed densities, Up - finds the gap in the up spin channel, Down - finds the gap in the down spin channel.
- Returns:
Tuple of floats in eV corresponding to the gap, cbm and vbm.
- Return type:
(gap, cbm, vbm)
- class FermiDos(dos: Dos, structure: Structure | None = None, nelecs: float | None = None, bandgap: float | None = None)[source]
Bases:
Dos
,MSONable
This wrapper class helps relate the density of states, doping levels (i.e. carrier concentrations) and corresponding fermi levels. A negative doping concentration indicates the majority carriers are electrons (n-type doping); a positive doping concentration indicates holes are the majority carriers (p-type doping).
- Parameters:
dos – Pymatgen Dos object.
structure – A structure. If not provided, the structure of the dos object will be used. If the dos does not have an associated structure object, an error will be thrown.
nelecs – The number of electrons included in the energy range of dos. It is used for normalizing the densities. Default is the total number of electrons in the structure.
bandgap – If set, the energy values are scissored so that the electronic band gap matches this value.
- get_doping(fermi_level: float, temperature: float) float [source]
Calculate the doping (majority carrier concentration) at a given Fermi level and temperature. A simple Left Riemann sum is used for integrating the density of states over energy & equilibrium Fermi-Dirac distribution.
- Parameters:
fermi_level – The fermi_level level in eV.
temperature – The temperature in Kelvin.
- Returns:
The doping concentration in units of 1/cm^3. Negative values indicate that the majority carriers are electrons (n-type doping) whereas positive values indicates the majority carriers are holes (p-type doping).
- get_fermi(concentration: float, temperature: float, rtol: float = 0.01, nstep: int = 50, step: float = 0.1, precision: int = 8) float [source]
Finds the Fermi level at which the doping concentration at the given temperature (T) is equal to concentration. A greedy algorithm is used where the relative error is minimized by calculating the doping at a grid which continually becomes finer.
- Parameters:
concentration – The doping concentration in 1/cm^3. Negative values represent n-type doping and positive values represent p-type doping.
temperature – The temperature in Kelvin.
rtol – The maximum acceptable relative error.
nstep – The number of steps checked around a given Fermi level.
step – Initial step in energy when searching for the Fermi level.
precision – Essentially the decimal places of calculated Fermi level.
- Raises:
ValueError – If the Fermi level cannot be found.
- Returns:
The Fermi level in eV. Note that this is different from the default dos.efermi.
- get_fermi_interextrapolated(concentration: float, temperature: float, warn: bool = True, c_ref: float = 10000000000.0, **kwargs) float [source]
Similar to get_fermi except that when get_fermi fails to converge, an interpolated or extrapolated fermi is returned with the assumption that the Fermi level changes linearly with log(abs(concentration)).
- Parameters:
concentration – The doping concentration in 1/cm^3. Negative values represent n-type doping and positive values represent p-type doping.
temperature – The temperature in Kelvin.
warn – Whether to give a warning the first time the fermi cannot be found.
c_ref – A doping concentration where get_fermi returns a value without error for both c_ref and -c_ref.
**kwargs – Keyword arguments passed to the get_fermi function.
- Returns:
The Fermi level. Note, the value is possibly interpolated or extrapolated and must be used with caution.
- class LobsterCompleteDos(structure: Structure, total_dos: Dos, pdoss: Mapping[PeriodicSite, Mapping[Orbital, Mapping[Spin, ArrayLike]]], normalize: bool = False)[source]
Bases:
CompleteDos
Extended CompleteDOS for Lobster.
- Parameters:
structure – Structure associated with this particular DOS.
total_dos – total Dos for structure
pdoss – The pdoss are supplied as an {Site: {Orbital: {Spin:Densities}}}
normalize – Whether to normalize the densities by the volume of the structure. If True, the units of the densities are states/eV/Angstrom^3. Otherwise, the units are states/eV.
- classmethod from_dict(dct) LobsterCompleteDos [source]
Hydrate CompleteDos object from dict representation.
- get_element_spd_dos(el: SpeciesLike) dict[str, Dos] [source]
Get element and spd projected Dos.
- Parameters:
el – Element in Structure.composition associated with LobsterCompleteDos
- Returns:
densities, OrbitalType.p: densities, OrbitalType.d: densities}
- Return type:
dict of {OrbitalType.s
- get_site_orbital_dos(site: PeriodicSite, orbital: str) Dos [source]
Get the Dos for a particular orbital of a particular site.
- Parameters:
site – Site in Structure associated with CompleteDos.
orbital – principal quantum number and orbital in string format, e.g. “4s”. possible orbitals are: “s”, “p_y”, “p_z”, “p_x”, “d_xy”, “d_yz”, “d_z^2”, “d_xz”, “d_x^2-y^2”, “f_y(3x^2-y^2)”, “f_xyz”, “f_yz^2”, “f_z^3”, “f_xz^2”, “f_z(x^2-y^2)”, “f_x(x^2-3y^2)” In contrast to the Cohpcar and the Cohplist objects, the strings from the Lobster files are used
- Returns:
Dos containing densities of an orbital of a specific site.
- get_site_t2g_eg_resolved_dos(site: PeriodicSite) dict[str, Dos] [source]
Get the t2g, eg projected DOS for a particular site.
- Parameters:
site – Site in Structure associated with CompleteDos.
- Returns:
Dos, “t2g”: Dos} containing summed e_g and t2g DOS for the site.
- Return type:
A dict {“e_g”
pymatgen.electronic_structure.plotter module
This module implements plotter for DOS and band structure.
- class BSDOSPlotter(bs_projection: Literal['elements'] | None = 'elements', dos_projection: str = 'elements', vb_energy_range: float = 4, cb_energy_range: float = 4, fixed_cb_energy: bool = False, egrid_interval: float = 1, font: str = 'Times New Roman', axis_fontsize: float = 20, tick_fontsize: float = 15, legend_fontsize: float = 14, bs_legend: str = 'best', dos_legend: str = 'best', rgb_legend: bool = True, fig_size: tuple[float, float] = (11, 8.5))[source]
Bases:
object
A joint, aligned band structure and density of states plot. Contributions from Jan Pohls as well as the online example from Germain Salvato-Vallverdu: http://gvallver.perso.univ-pau.fr/?p=587.
Instantiate plotter settings.
- Parameters:
bs_projection ('elements' | None) – Whether to project the bands onto elements.
dos_projection (str) – “elements”, “orbitals”, or None
vb_energy_range (float) – energy in eV to show of valence bands
cb_energy_range (float) – energy in eV to show of conduction bands
fixed_cb_energy (bool) – If true, the cb_energy_range will be interpreted as constant (i.e., no gap correction for cb energy)
egrid_interval (float) – interval for grid marks
font (str) – font family
axis_fontsize (float) – font size for axis
tick_fontsize (float) – font size for axis tick labels
legend_fontsize (float) – font size for legends
bs_legend (str) – matplotlib string location for legend or None
dos_legend (str) – matplotlib string location for legend or None
rgb_legend (bool) – (T/F) whether to draw RGB triangle/bar for element proj.
fig_size (tuple) – dimensions of figure size (width, height)
- get_plot(bs: BandStructureSymmLine, dos: Dos | CompleteDos | None = None) plt.Axes | tuple[plt.Axes, plt.Axes] [source]
Get a matplotlib plot object.
- Parameters:
bs (BandStructureSymmLine) – the bandstructure to plot. Projection data must exist for projected plots.
dos (Dos) – the Dos to plot. Projection data must exist (i.e., CompleteDos) for projected plots.
- Returns:
matplotlib axes for the band structure and DOS, resp.
- Return type:
plt.Axes | tuple[plt.Axes, plt.Axes]
- class BSPlotter(bs: BandStructureSymmLine)[source]
Bases:
object
Class to plot or get data to facilitate the plot of band structure objects.
- Parameters:
bs – A BandStructureSymmLine object.
- add_bs(bs: BandStructureSymmLine | list[BandStructureSymmLine]) None [source]
Method to add bands objects to the BSPlotter.
- bs_plot_data(zero_to_efermi=True, bs=None, bs_ref=None, split_branches=True)[source]
Get the data nicely formatted for a plot.
- Parameters:
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
bs – the bandstructure to get the data from. If not provided, the first one in the self._bs list will be used.
bs_ref – is the bandstructure of reference when a rescale of the distances is need to plot multiple bands
split_branches – if True distances and energies are split according to the branches. If False distances and energies are split only where branches are discontinuous (reducing the number of lines to plot).
- Returns:
A dictionary of the following format: ticks: A dict with the ‘distances’ at which there is a kpoint (the x axis) and the labels (None if no label). energy: A dict storing bands for spin up and spin down data {Spin:[np.array(nb_bands,kpoints),…]} as a list of discontinuous kpath of energies. The energy of multiple continuous branches are stored together. vbm: A list of tuples (distance,energy) marking the vbms. The energies are shifted with respect to the Fermi level is the option has been selected. cbm: A list of tuples (distance,energy) marking the cbms. The energies are shifted with respect to the Fermi level is the option has been selected. lattice: The reciprocal lattice. zero_energy: This is the energy used as zero for the plot. band_gap:A string indicating the band gap and its nature (empty if it’s a metal). is_metal: True if the band structure is metallic (i.e., there is at least one band crossing the Fermi level).
- Return type:
dict
- get_plot(zero_to_efermi=True, ylim=None, smooth=False, vbm_cbm_marker=False, smooth_tol=0, smooth_k=3, smooth_np=100, bs_labels=None)[source]
Get a matplotlib object for the bandstructures plot. Multiple bandstructure objs are plotted together if they have the same high symm path.
- Parameters:
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
ylim – Specify the y-axis (energy) limits; by default None let the code choose. It is vbm-4 and cbm+4 if insulator efermi-10 and efermi+10 if metal
smooth (bool or list(bools)) – interpolates the bands by a spline cubic. A single bool values means to interpolate all the bandstructure objs. A list of bools allows to select the bandstructure obs to interpolate.
vbm_cbm_marker (bool) – if True, a marker is added to the vbm and cbm.
smooth_tol (float) – tolerance for fitting spline to band data. Default is None such that no tolerance will be used.
smooth_k (int) – degree of splines 1<k<5
smooth_np (int) – number of interpolated points per each branch.
bs_labels – labels for each band for the plot legend.
- get_ticks()[source]
Get all ticks and labels for a band structure plot.
- Returns:
A dictionary with ‘distance’: a list of distance at which ticks should be set and ‘label’: a list of label for each of those ticks.
- Return type:
dict
- get_ticks_old()[source]
Get all ticks and labels for a band structure plot.
- Returns:
A dictionary with ‘distance’: a list of distance at which ticks should be set and ‘label’: a list of label for each of those ticks.
- Return type:
dict
- plot_brillouin()[source]
Plot the Brillouin zone.
- Returns:
A matplotlib figure object with the Brillouin zone.
- Return type:
plt.Figure
- plot_compare(other_plotter, legend=True) Axes [source]
Plot two band structure for comparison. One is in red the other in blue (no difference in spins). The two band structures need to be defined on the same symmetry lines! and the distance between symmetry lines is the one of the band structure used to build the BSPlotter.
- Parameters:
other_plotter – Another band structure object defined along the same symmetry lines
legend – True to add a legend to the plot
- Returns:
matplotlib Axes object with both band structures
- Return type:
plt.Axes
- save_plot(filename: str, ylim=None, zero_to_efermi=True, smooth=False) None [source]
Save matplotlib plot to a file.
- Parameters:
filename (str) – Filename to write to. Must include extension to specify image format.
ylim – Specifies the y-axis limits.
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
smooth – Cubic spline interpolation of the bands.
- show(zero_to_efermi=True, ylim=None, smooth=False, smooth_tol=None) None [source]
Show the plot using matplotlib.
- Parameters:
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
ylim – Specify the y-axis (energy) limits; by default None let the code choose. It is vbm-4 and cbm+4 if insulator efermi-10 and efermi+10 if metal
smooth – interpolates the bands by a spline cubic
smooth_tol (float) – tolerance for fitting spline to band data. Default is None such that no tolerance will be used.
- class BSPlotterProjected(bs)[source]
Bases:
BSPlotter
Class to plot or get data to facilitate the plot of band structure objects projected along orbitals, elements or sites.
- Parameters:
bs – A BandStructureSymmLine object with projections.
- get_elt_projected_plots(zero_to_efermi: bool = True, ylim=None, vbm_cbm_marker: bool = False) plt.Axes [source]
Method returning a plot composed of subplots along different elements.
- Returns:
- 2x2 array of plt.Axes with different subfigures for each projection
The blue and red colors are for spin up and spin down The bigger the red or blue dot in the band structure the higher character for the corresponding element and orbital
- Return type:
np.ndarray[plt.Axes]
- get_elt_projected_plots_color(zero_to_efermi=True, elt_ordered=None)[source]
Returns a pyplot plot object with one plot where the band structure line color depends on the character of the band (along different elements). Each element is associated with red, green or blue and the corresponding rgb color depending on the character of the band is used. The method can only deal with binary and ternary compounds.
Spin up and spin down are differentiated by a ‘-’ and a ‘–’ line.
- Parameters:
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
elt_ordered – A list of Element ordered. The first one is red, second green, last blue.
- Raises:
ValueError – if the number of elements is not 2 or 3.
- Returns:
a pyplot object
- get_projected_plots_dots(dictio, zero_to_efermi=True, ylim=None, vbm_cbm_marker=False)[source]
Method returning a plot composed of subplots along different elements and orbitals.
- Parameters:
dictio – The element and orbitals you want a projection on. The format is {Element:[Orbitals]} for instance {‘Cu’:[‘d’,’s’],’O’:[‘p’]} will give projections for Cu on d and s orbitals and on oxygen p. If you use this class to plot LobsterBandStructureSymmLine, the orbitals are named as in the FATBAND filename, e.g. “2p” or “2p_x”
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
ylim – Specify the y-axis limits. Defaults to None.
vbm_cbm_marker – Add markers for the VBM and CBM. Defaults to False.
- Returns:
a pyplot object with different subfigures for each projection The blue and red colors are for spin up and spin down. The bigger the red or blue dot in the band structure the higher character for the corresponding element and orbital.
- get_projected_plots_dots_patom_pmorb(dictio, dictpa, sum_atoms=None, sum_morbs=None, zero_to_efermi=True, ylim=None, vbm_cbm_marker=False, selected_branches=None, w_h_size=(12, 8), num_column=None)[source]
Method returns a plot composed of subplots for different atoms and orbitals (subshell orbitals such as ‘s’, ‘p’, ‘d’ and ‘f’ defined by azimuthal quantum numbers l = 0, 1, 2 and 3, respectively or individual orbitals like ‘px’, ‘py’ and ‘pz’ defined by magnetic quantum numbers m = -1, 1 and 0, respectively). This is an extension of “get_projected_plots_dots” method.
- Parameters:
dictio – The elements and the orbitals you need to project on. The format is {Element:[Orbitals]}, for instance: {‘Cu’:[‘dxy’,’s’,’px’],’O’:[‘px’,’py’,’pz’]} will give projections for Cu on orbitals dxy, s, px and for O on orbitals px, py, pz. If you want to sum over all individual orbitals of subshell orbitals, for example, ‘px’, ‘py’ and ‘pz’ of O, just simply set {‘Cu’:[‘dxy’,’s’,’px’],’O’:[‘p’]} and set sum_morbs (see explanations below) as {‘O’:[p],…}. Otherwise, you will get an error.
dictpa – The elements and their sites (defined by site numbers) you need to project on. The format is {Element: [Site numbers]}, for instance: {‘Cu’:[1,5],’O’:[3,4]} will give projections for Cu on site-1 and on site-5, O on site-3 and on site-4 in the cell. The correct site numbers of atoms are consistent with themselves in the structure computed. Normally, the structure should be totally similar with POSCAR file, however, sometimes VASP can rotate or translate the cell. Thus, it would be safe if using Vasprun class to get the final_structure and as a result, correct index numbers of atoms.
sum_atoms – Sum projection of the similar atoms together (e.g.: Cu on site-1 and Cu on site-5). The format is {Element: [Site numbers]}, for instance: {‘Cu’: [1,5], ‘O’: [3,4]} means summing projections over Cu on site-1 and Cu on site-5 and O on site-3 and on site-4. If you do not want to use this functional, just turn it off by setting sum_atoms = None.
sum_morbs – Sum projections of individual orbitals of similar atoms together (e.g.: ‘dxy’ and ‘dxz’). The format is {Element: [individual orbitals]}, for instance: {‘Cu’: [‘dxy’, ‘dxz’], ‘O’: [‘px’, ‘py’]} means summing projections over ‘dxy’ and ‘dxz’ of Cu and ‘px’ and ‘py’ of O. If you do not want to use this functional, just turn it off by setting sum_morbs = None.
zero_to_efermi – Automatically set the Fermi level as the plot’s origin (i.e. subtract E - E_f). Defaults to True.
ylim – The y-axis limit. Defaults to None.
vbm_cbm_marker – Whether to plot points to indicate valence band maxima and conduction band minima positions. Defaults to False.
selected_branches – The index of symmetry lines you chose for plotting. This can be useful when the number of symmetry lines (in KPOINTS file) are manny while you only want to show for certain ones. The format is [index of line], for instance: [1, 3, 4] means you just need to do projection along lines number 1, 3 and 4 while neglecting lines number 2 and so on. By default, this is None type and all symmetry lines will be plotted.
w_h_size – This variable help you to control the width and height of figure. By default, width = 12 and height = 8 (inches). The width/height ratio is kept the same for subfigures and the size of each depends on how many number of subfigures are plotted.
num_column – This variable help you to manage how the subfigures are arranged in the figure by setting up the number of columns of subfigures. The value should be an int number. For example, num_column = 3 means you want to plot subfigures in 3 columns. By default, num_column = None and subfigures are aligned in 2 columns.
- Returns:
A pyplot object with different subfigures for different projections. The blue and red colors lines are bands for spin up and spin down. The green and cyan dots are projections for spin up and spin down. The bigger the green or cyan dots in the projected band structures, the higher character for the corresponding elements and orbitals. List of individual orbitals and their numbers (set up by VASP and no special meaning): s = 0; py = 1 pz = 2 px = 3; dxy = 4 dyz = 5 dz2 = 6 dxz = 7 dx2 = 8; f_3 = 9 f_2 = 10 f_1 = 11 f0 = 12 f1 = 13 f2 = 14 f3 = 15
- class BoltztrapPlotter(bz)[source]
Bases:
object
class containing methods to plot the data from Boltztrap.
- Parameters:
bz – a BoltztrapAnalyzer object.
- plot_carriers(temp=300)[source]
Plot the carrier concentration in function of Fermi level.
- Parameters:
temp – the temperature
- Returns:
a matplotlib object
- plot_complexity_factor_mu(temps=(300,), output='average', Lambda=0.5)[source]
Plot respect to the chemical potential of the Fermi surface complexity factor calculated as explained in Ref. Gibbs, Z. M. et al., Effective mass and fermi surface complexity factor from ab initio band structure calculations. npj Computational Materials 3, 8 (2017).
- Parameters:
output – ‘average’ returns the complexity factor calculated using the average of the three diagonal components of the seebeck and conductivity tensors. ‘tensor’ returns the complexity factor respect to the three diagonal components of seebeck and conductivity tensors.
temps – list of temperatures of calculated seebeck and conductivity.
Lambda – fitting parameter used to model the scattering (0.5 means constant relaxation time).
- Returns:
a matplotlib object
- plot_conductivity_dop(temps='all', output='average', relaxation_time=1e-14)[source]
Plot the conductivity in function of doping levels for different temperatures.
- Parameters:
temps – the default ‘all’ plots all the temperatures in the analyzer. Specify a list of temperatures if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Returns:
a matplotlib object
- plot_conductivity_mu(temp: float = 600, output: str = 'eig', relaxation_time: float = 1e-14, xlim: Sequence[float] | None = None)[source]
Plot the conductivity in function of Fermi level. Semi-log plot.
- Parameters:
temp (float) – the temperature
output (str) – “eig” or “average”
relaxation_time (float) – A relaxation time in s. Defaults to 1e-14 and the plot is in units of relaxation time
xlim (tuple[float, float]) – a 2-tuple of min and max fermi energy. Defaults to (0, band gap)
- Returns:
a matplotlib object
- plot_conductivity_temp(doping='all', output='average', relaxation_time=1e-14)[source]
Plot the conductivity in function of temperature for different doping levels.
- Parameters:
doping (str) – the default ‘all’ plots all the doping levels in the analyzer. Specify a list of doping levels if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Returns:
a matplotlib object
- plot_eff_mass_dop(temps='all', output='average')[source]
Plot the average effective mass in function of doping levels for different temperatures.
- Parameters:
temps – the default ‘all’ plots all the temperatures in the analyzer. Specify a list of temperatures if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Returns:
a matplotlib object
- plot_eff_mass_temp(doping='all', output: Literal['average', 'eigs'] = 'average')[source]
Plot the average effective mass in function of temperature for different doping levels.
- Parameters:
doping (str) – the default ‘all’ plots all the doping levels in the analyzer. Specify a list of doping levels if you want to plot only some.
output ('average' | 'eigs') – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
- Returns:
a matplotlib Axes object
- plot_hall_carriers(temp=300)[source]
Plot the Hall carrier concentration in function of Fermi level.
- Parameters:
temp – the temperature
- Returns:
a matplotlib object
- plot_power_factor_dop(temps='all', output='average', relaxation_time=1e-14)[source]
Plot the Power Factor in function of doping levels for different temperatures.
- Parameters:
temps – the default ‘all’ plots all the temperatures in the analyzer. Specify a list of temperatures if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Returns:
a matplotlib object
- plot_power_factor_mu(temp: float = 600, output: str = 'eig', relaxation_time: float = 1e-14, xlim: Sequence[float] | None = None)[source]
Plot the power factor in function of Fermi level. Semi-log plot.
- Parameters:
temp (float) – the temperature
output (str) – “eig” or “average”
relaxation_time (float) – A relaxation time in s. Defaults to 1e-14 and the plot is in units of relaxation time
xlim (tuple[float, float]) – a 2-tuple of min and max fermi energy. Defaults to (0, band gap)
- Returns:
a matplotlib object
- plot_power_factor_temp(doping='all', output='average', relaxation_time=1e-14)[source]
Plot the Power Factor in function of temperature for different doping levels.
- Parameters:
doping (str) – the default ‘all’ plots all the doping levels in the analyzer. Specify a list of doping levels if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Returns:
a matplotlib object
- plot_seebeck_dop(temps='all', output='average')[source]
Plot the Seebeck in function of doping levels for different temperatures.
- Parameters:
temps – the default ‘all’ plots all the temperatures in the analyzer. Specify a list of temperatures if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
- Returns:
a matplotlib object
- plot_seebeck_eff_mass_mu(temps=(300,), output='average', Lambda=0.5)[source]
Plot respect to the chemical potential of the Seebeck effective mass calculated as explained in Ref. Gibbs, Z. M. et al., Effective mass and fermi surface complexity factor from ab initio band structure calculations. npj Computational Materials 3, 8 (2017).
- Parameters:
output – ‘average’ returns the seebeck effective mass calculated using the average of the three diagonal components of the seebeck tensor. ‘tensor’ returns the seebeck effective mass respect to the three diagonal components of the seebeck tensor.
temps – list of temperatures of calculated seebeck.
Lambda – fitting parameter used to model the scattering (0.5 means constant relaxation time).
- Returns:
a matplotlib object
- plot_seebeck_mu(temp: float = 600, output: str = 'eig', xlim: Sequence[float] | None = None)[source]
Plot the seebeck coefficient in function of Fermi level.
- Parameters:
temp (float) – the temperature
output (str) – “eig” or “average”
xlim (tuple[float, float]) – a 2-tuple of min and max fermi energy. Defaults to (0, band gap)
- Returns:
a matplotlib object
- plot_seebeck_temp(doping='all', output='average')[source]
Plot the Seebeck coefficient in function of temperature for different doping levels.
- Parameters:
doping (str) – the default ‘all’ plots all the doping levels in the analyzer. Specify a list of doping levels if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
- Returns:
a matplotlib object
- plot_zt_dop(temps='all', output='average', relaxation_time=1e-14)[source]
Plot the figure of merit zT in function of doping levels for different temperatures.
- Parameters:
temps – the default ‘all’ plots all the temperatures in the analyzer. Specify a list of temperatures if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Returns:
a matplotlib object
- plot_zt_mu(temp: float = 600, output: str = 'eig', relaxation_time: float = 1e-14, xlim: Sequence[float] | None = None) plt.Axes [source]
Plot the ZT as function of Fermi level.
- Parameters:
temp (float) – the temperature
output (str) – “eig” or “average”
relaxation_time (float) – A relaxation time in s. Defaults to 1e-14 and the plot is in units of relaxation time
xlim (tuple[float, float]) – a 2-tuple of min and max fermi energy. Defaults to (0, band gap)
- Returns:
matplotlib axes object
- Return type:
plt.Axes
- plot_zt_temp(doping='all', output: Literal['average', 'eigs'] = 'average', relaxation_time=1e-14)[source]
Plot the figure of merit zT in function of temperature for different doping levels.
- Parameters:
doping (str) – the default ‘all’ plots all the doping levels in the analyzer. Specify a list of doping levels if you want to plot only some.
output – with ‘average’ you get an average of the three directions with ‘eigs’ you get all the three directions.
relaxation_time – specify a constant relaxation time value
- Raises:
ValueError – if output is not ‘average’ or ‘eigs’
- Returns:
a matplotlib object
- class CohpPlotter(zero_at_efermi=True, are_coops=False, are_cobis=False)[source]
Bases:
object
Class for plotting crystal orbital Hamilton populations (COHPs) or crystal orbital overlap populations (COOPs). It is modeled after the DosPlotter object.
- Parameters:
zero_at_efermi – Whether to shift all populations to have zero energy at the Fermi level. Defaults to True.
are_coops – Switch to indicate that these are COOPs, not COHPs. Defaults to False for COHPs.
are_cobis – Switch to indicate that these are COBIs or multi-center COBIs, not COHPs/COOPs. Defaults to False for COHPs.
- add_cohp(label, cohp) None [source]
Adds a COHP for plotting.
- Parameters:
label – Label for the COHP. Must be unique.
cohp – COHP object.
- add_cohp_dict(cohp_dict, key_sort_func=None) None [source]
Adds a dictionary of COHPs with an optional sorting function for the keys.
- Parameters:
cohp_dict – dict of the form {label: Cohp}
key_sort_func – function used to sort the cohp_dict keys.
- get_cohp_dict()[source]
Returns the added COHPs as a json-serializable dict. Note that if you have specified smearing for the COHP plot, the populations returned will be the smeared and not the original populations.
- Returns:
Dict of COHP data of the form {label: {“efermi”: efermi, “energies”: …, “COHP”: {Spin.up: …}, “ICOHP”: …}}.
- Return type:
dict
- get_plot(xlim=None, ylim=None, plot_negative=None, integrated=False, invert_axes=True)[source]
Get a matplotlib plot showing the COHP.
- Parameters:
xlim – Specifies the x-axis limits. Defaults to None for automatic determination.
ylim – Specifies the y-axis limits. Defaults to None for automatic determination.
plot_negative – It is common to plot -COHP(E) so that the sign means the same for COOPs and COHPs. Defaults to None for automatic determination: If are_coops is True, this will be set to False, else it will be set to True.
integrated – Switch to plot ICOHPs. Defaults to False.
invert_axes – Put the energies onto the y-axis, which is common in chemistry.
- Returns:
A matplotlib object.
- save_plot(filename: str, xlim=None, ylim=None) None [source]
Save matplotlib plot to a file.
- Parameters:
filename (str) – File name to write to. Must include extension to specify image format.
xlim – Specifies the x-axis limits. Defaults to None for automatic determination.
ylim – Specifies the y-axis limits. Defaults to None for automatic determination.
- class DosPlotter(zero_at_efermi: bool = True, stack: bool = False, sigma: float | None = None)[source]
Bases:
object
Class for plotting phonon DOSs. The interface is extremely flexible given there are many different ways in which people want to view DOS. Typical usage is:
# Initializes plotter with some optional args. Defaults are usually fine plotter = PhononDosPlotter().
# Add DOS with a label plotter.add_dos(“Total DOS”, dos)
# Alternatively, you can add a dict of DOSes. This is the typical form # returned by CompletePhononDos.get_element_dos(). plotter.add_dos_dict({“dos1”: dos1, “dos2”: dos2}) plotter.add_dos_dict(complete_dos.get_spd_dos())
- Parameters:
zero_at_efermi (bool) – Whether to shift all Dos to have zero energy at the fermi energy. Defaults to True.
stack (bool) – Whether to plot the DOS as a stacked area graph
sigma (float) – Specify a standard deviation for Gaussian smearing the DOS for nicer looking plots. Defaults to None for no smearing.
- add_dos(label: str, dos: Dos) None [source]
Adds a dos for plotting.
- Parameters:
label – label for the DOS. Must be unique.
dos – Dos object
- add_dos_dict(dos_dict, key_sort_func=None) None [source]
Add a dictionary of doses, with an optional sorting function for the keys.
- Parameters:
dos_dict – dict of {label: Dos}
key_sort_func – function used to sort the dos_dict keys.
- get_dos_dict()[source]
Returns the added doses as a json-serializable dict. Note that if you have specified smearing for the DOS plot, the densities returned will be the smeared densities, not the original densities.
- Returns:
Dict of dos data. Generally of the form {label: {‘energies’:…, ‘densities’: {‘up’:…}, ‘efermi’:efermi}}
- Return type:
dict
- get_plot(xlim: tuple[float, float] | None = None, ylim: tuple[float, float] | None = None, invert_axes: bool = False, beta_dashed: bool = False) plt.Axes [source]
Get a matplotlib plot showing the DOS.
- Parameters:
xlim (tuple[float, float]) – The energy axis limits. Defaults to None for automatic determination.
ylim (tuple[float, float]) – The y-axis limits. Defaults to None for automatic determination.
invert_axes (bool) – Whether to invert the x and y axes. Enables chemist style DOS plotting. Defaults to False.
beta_dashed (bool) – Plots the beta spin channel with a dashed line. Defaults to False.
- Returns:
matplotlib Axes object.
- Return type:
plt.Axes
- save_plot(filename: str, xlim=None, ylim=None, invert_axes=False, beta_dashed=False) None [source]
Save matplotlib plot to a file.
- Parameters:
filename (str) – Filename to write to. Must include extension to specify image format.
xlim – Specifies the x-axis limits. Set to None for automatic determination.
ylim – Specifies the y-axis limits.
invert_axes (bool) – Whether to invert the x and y axes. Enables chemist style DOS plotting. Defaults to False.
beta_dashed (bool) – Plots the beta spin channel with a dashed line. Defaults to False.
- show(xlim=None, ylim=None, invert_axes=False, beta_dashed=False) None [source]
Show the plot using matplotlib.
- Parameters:
xlim – Specifies the x-axis limits. Set to None for automatic determination.
ylim – Specifies the y-axis limits.
invert_axes (bool) – Whether to invert the x and y axes. Enables chemist style DOS plotting. Defaults to False.
beta_dashed (bool) – Plots the beta spin channel with a dashed line. Defaults to False.
- fold_point(p, lattice, coords_are_cartesian=False)[source]
Folds a point with coordinates p inside the first Brillouin zone of the lattice.
- Parameters:
p – coordinates of one point
lattice – Lattice object used to convert from reciprocal to Cartesian coordinates
coords_are_cartesian – Set to True if you are providing coordinates in Cartesian coordinates. Defaults to False.
- Returns:
The Cartesian coordinates folded inside the first Brillouin zone
- plot_brillouin_zone(bz_lattice, lines=None, labels=None, kpoints=None, fold=False, coords_are_cartesian: bool = False, ax: Axes = None, **kwargs)[source]
Plots a 3D representation of the Brillouin zone of the structure. Can add to the plot paths, labels and kpoints.
- Parameters:
bz_lattice – Lattice object of the Brillouin zone
lines – list of lists of coordinates. Each list represent a different path
labels – dict containing the label as a key and the coordinates as value.
kpoints – list of coordinates
fold – whether the points should be folded inside the first Brillouin Zone. Defaults to False. Requires lattice if True.
coords_are_cartesian – Set to True if you are providing coordinates in Cartesian coordinates. Defaults to False.
ax – matplotlib Axes or None if a new figure should be created.
kwargs – provided by add_fig_kwargs decorator
- Returns:
matplotlib figure
Keyword arguments controlling the display of the figure:
kwargs
Meaning
title
Title of the plot (Default: None).
show
True to show the figure (default: True).
savefig
”abc.png” or “abc.eps” to save the figure to a file.
size_kwargs
Dictionary with options passed to fig.set_size_inches e.g. size_kwargs=dict(w=3, h=4)
tight_layout
True to call fig.tight_layout (default: False)
ax_grid
True (False) to add (remove) grid from all axes in fig. Default: None i.e. fig is left unchanged.
ax_annotate
Add labels to subplots e.g. (a), (b). Default: False
fig_close
Close figure. Default: False.
- plot_brillouin_zone_from_kpath(kpath, ax: Axes = None, **kwargs) Axes [source]
- Gives the plot (as a matplotlib object) of the symmetry line path in
the Brillouin Zone.
- Parameters:
kpath (HighSymmKpath) – a HighSymmKPath object
ax – matplotlib Axes or None if a new figure should be created.
**kwargs – provided by add_fig_kwargs decorator
- Returns:
matplotlib Axes
Keyword arguments controlling the display of the figure:
kwargs
Meaning
title
Title of the plot (Default: None).
show
True to show the figure (default: True).
savefig
”abc.png” or “abc.eps” to save the figure to a file.
size_kwargs
Dictionary with options passed to fig.set_size_inches e.g. size_kwargs=dict(w=3, h=4)
tight_layout
True to call fig.tight_layout (default: False)
ax_grid
True (False) to add (remove) grid from all axes in fig. Default: None i.e. fig is left unchanged.
ax_annotate
Add labels to subplots e.g. (a), (b). Default: False
fig_close
Close figure. Default: False.
- Return type:
plt.Axes
- plot_ellipsoid(hessian, center, lattice=None, rescale=1.0, ax: Axes = None, coords_are_cartesian=False, arrows=False, **kwargs)[source]
Plots a 3D ellipsoid rappresenting the Hessian matrix in input. Useful to get a graphical visualization of the effective mass of a band in a single k-point.
- Parameters:
hessian – the Hessian matrix
center – the center of the ellipsoid in reciprocal coords (Default)
lattice – Lattice object of the Brillouin zone
rescale – factor for size scaling of the ellipsoid
ax – matplotlib Axes or None if a new figure should be created.
coords_are_cartesian – Set to True if you are providing a center in Cartesian coordinates. Defaults to False.
arrows – whether to plot arrows for the principal axes of the ellipsoid. Defaults to False.
**kwargs – passed to the matplotlib function ‘plot_wireframe’. Color defaults to blue, rstride and cstride default to 4, alpha defaults to 0.2.
- Returns:
matplotlib figure and matplotlib ax
- Example of use:
fig,ax=plot_wigner_seitz(struct.reciprocal_lattice) plot_ellipsoid(hessian,[0.0,0.0,0.0], struct.reciprocal_lattice,ax=ax)
- plot_fermi_surface(data, structure, cbm, energy_levels=None, multiple_figure=True, mlab_figure=None, kpoints_dict=None, colors=None, transparency_factor=None, labels_scale_factor=0.05, points_scale_factor=0.02, interactive=True)[source]
Plot the Fermi surface at specific energy value using Boltztrap 1 FERMI mode.
The easiest way to use this plotter is:
Run boltztrap in ‘FERMI’ mode using BoltztrapRunner,
Load BoltztrapAnalyzer using your method of choice (e.g., from_files)
- Pass in your BoltztrapAnalyzer’s fermi_surface_data as this
function’s data argument.
- Parameters:
data – energy values in a 3D grid from a CUBE file via read_cube_file function, or from a BoltztrapAnalyzer.fermi_surface_data
structure – structure object of the material
energy_levels ([float]) – Energy values for plotting the fermi surface(s) By default 0 eV correspond to the VBM, as in the plot of band structure along symmetry line. Default: One surface, with max energy value + 0.01 eV
cbm (bool) – Boolean value to specify if the considered band is a conduction band or not
multiple_figure (bool) – If True a figure for each energy level will be shown. If False all the surfaces will be shown in the same figure. In this last case, tune the transparency factor.
mlab_figure (mayavi.mlab.figure) – A previous figure to plot a new surface on.
kpoints_dict (dict) – dictionary of kpoints to label in the plot. Example: {“K”:[0.5,0.0,0.5]}, coords are fractional
colors ([tuple]) – Iterable of 3-tuples (r,g,b) of integers to define the colors of each surface (one per energy level). Should be the same length as the number of surfaces being plotted. Example (3 surfaces): colors=[(1,0,0), (0,1,0), (0,0,1)] Example (2 surfaces): colors=[(0, 0.5, 0.5)]
transparency_factor (float) – Values in the range [0,1] to tune the opacity of each surface. Should be one transparency_factor per surface.
labels_scale_factor (float) – factor to tune size of the kpoint labels
points_scale_factor (float) – factor to tune size of the kpoint points
interactive (bool) – if True an interactive figure will be shown. If False a non interactive figure will be shown, but it is possible to plot other surfaces on the same figure. To make it interactive, run mlab.show().
- Returns:
- The mlab plotter and an interactive
figure to control the plot.
- Return type:
((mayavi.mlab.figure, mayavi.mlab))
- Note: Experimental.
Please, double check the surface shown by using some other software and report issues.
- plot_labels(labels, lattice=None, coords_are_cartesian=False, ax: Axes = None, **kwargs)[source]
Adds labels to a matplotlib Axes.
- Parameters:
labels – dict containing the label as a key and the coordinates as value.
lattice – Lattice object used to convert from reciprocal to Cartesian coordinates
coords_are_cartesian – Set to True if you are providing. coordinates in Cartesian coordinates. Defaults to False. Requires lattice if False.
ax – matplotlib Axes or None if a new figure should be created.
kwargs – kwargs passed to the matplotlib function ‘text’. Color defaults to blue and size to 25.
- Returns:
matplotlib figure and matplotlib ax
- plot_lattice_vectors(lattice, ax: Axes = None, **kwargs)[source]
Adds the basis vectors of the lattice provided to a matplotlib Axes.
- Parameters:
lattice – Lattice object
ax – matplotlib Axes or None if a new figure should be created.
kwargs – kwargs passed to the matplotlib function ‘plot’. Color defaults to green and linewidth to 3.
- Returns:
matplotlib figure and matplotlib ax
- plot_path(line, lattice=None, coords_are_cartesian=False, ax: Axes = None, **kwargs)[source]
Adds a line passing through the coordinates listed in ‘line’ to a matplotlib Axes.
- Parameters:
line – list of coordinates.
lattice – Lattice object used to convert from reciprocal to Cartesian coordinates
coords_are_cartesian – Set to True if you are providing coordinates in Cartesian coordinates. Defaults to False. Requires lattice if False.
ax – matplotlib Axes or None if a new figure should be created.
kwargs – kwargs passed to the matplotlib function ‘plot’. Color defaults to red and linewidth to 3.
- Returns:
matplotlib figure and matplotlib ax
- plot_points(points, lattice=None, coords_are_cartesian=False, fold=False, ax: Axes = None, **kwargs)[source]
Adds Points to a matplotlib Axes.
- Parameters:
points – list of coordinates
lattice – Lattice object used to convert from reciprocal to Cartesian coordinates
coords_are_cartesian – Set to True if you are providing coordinates in Cartesian coordinates. Defaults to False. Requires lattice if False.
fold – whether the points should be folded inside the first Brillouin Zone. Defaults to False. Requires lattice if True.
ax – matplotlib Axes or None if a new figure should be created.
kwargs – kwargs passed to the matplotlib function ‘scatter’. Color defaults to blue
- Returns:
matplotlib figure and matplotlib ax
- plot_wigner_seitz(lattice, ax: Axes = None, **kwargs)[source]
Adds the skeleton of the Wigner-Seitz cell of the lattice to a matplotlib Axes.
- Parameters:
lattice – Lattice object
ax – matplotlib Axes or None if a new figure should be created.
kwargs – kwargs passed to the matplotlib function ‘plot’. Color defaults to black and linewidth to 1.
- Returns:
matplotlib figure and matplotlib ax