pymatgen.analysis.magnetism.jahnteller module

class JahnTellerAnalyzer[source]

Bases: object

Will attempt to classify if structure may be Jahn-Teller active.

Class currently uses datafile of hard-coded common Jahn-Teller active ions.

If structure is annotated with magnetic moments, will estimate if structure may be high-spin or low-spin.

Class aims for more false-positives than false-negatives.

get_analysis(structure, calculate_valences=True, guesstimate_spin=False)[source]
get_analysis_and_structure(structure, calculate_valences=True, guesstimate_spin=False, op_threshold=0.1)[source]

Obtain an analysis of a given structure and if it may be Jahn-Teller active or not. This is a heuristic, and may give false positives and false negatives (false positives are preferred).

  • structure – input structure
  • (bool) (calculate_valences) – whether to attempt to calculate valences or not, structure

should have oxidation states to perform analysis :param guesstimate_spin (bool): whether to guesstimate spin state from magnetic moments or not, use with caution :param op_threshold (float): threshold for order parameter above which to consider site to match an octahedral or tetrahedral motif, since Jahn-Teller structures can often be quite distorted, this threshold is smaller than one might expect :return (dict): analysis of structure, with key ‘strength’ which may be ‘none’, ‘strong’, ‘weak’, or ‘unknown’

get_magnitude_of_effect_from_species(species, spin_state, motif)[source]

Get magnitude of Jahn-Teller effect from provided species, spin state and motife.

  • species – e.g. Fe2+
  • (str) (motif) – “high” or “low”
  • (str) – “oct” or “tet”
Return (str):
static get_magnitude_of_effect_from_spin_config(spin_config)[source]

Roughly, the magnitude of Jahn-Teller distortion will be: * in octahedral environments, strong if e_g orbitals unevenly occupied but weak if t_2g orbitals unevenly occupied * in tetrahedral environments always weaker :param motif (str): “oct” or “tet” :param spin_config (dict): dict of ‘e’ (e_g) and ‘t’ (t2_g) with number of electrons in each state

is_jahn_teller_active(structure, calculate_valences=True)[source]
static mu_so(motif, spin_state)[source]

Calculates the spin-only magnetic moment for a given species. Only supports transition metals.

  • species – str or Species
  • motif – “oct” or “tet”
  • spin_state – “high” or “low”

spin-only magnetic moment in Bohr magnetons