pymatgen.command_line.mcsqs_caller module

Module to call mcsqs, distributed with AT-AT https://www.brown.edu/Departments/Engineering/Labs/avdw/atat/

class Sqs(bestsqs: pymatgen.core.structure.Structure, objective_function: Union[float, str], allsqs: List, directory: str)[source]

Bases: tuple

Return type for run_mcsqs.

Create new instance of Sqs(bestsqs, objective_function, allsqs, directory)

allsqs: List[source]

Alias for field number 2

bestsqs: pymatgen.core.structure.Structure[source]

Alias for field number 0

directory: str[source]

Alias for field number 3

objective_function: Union[float, str][source]

Alias for field number 1

run_mcsqs(*args, **kwargs)pymatgen.command_line.mcsqs_caller.Sqs[source]

Helper function for calling mcsqs with different arguments :param structure: Disordered pymatgen Structure object :type structure: Structure :param clusters: Dictionary of cluster interactions with entries in the form

number of atoms: cutoff in angstroms

Parameters

scaling (int or list) –

Scaling factor to determine supercell. Two options are possible: a. (preferred) Scales number of atoms, e.g., for a structure with 8 atoms,

scaling=4 would lead to a 32 atom supercell

  1. A sequence of three scaling factors, e.g., [2, 1, 1], which specifies that the supercell should have dimensions 2a x b x c

Keyword Arguments
  • search_time (float) – Time spent looking for the ideal SQS in minutes (default: 60)

  • directory (str) – Directory to run mcsqs calculation and store files (default: None runs calculations in a temp directory)

  • instances (int) – Specifies the number of parallel instances of mcsqs to run (default: number of cpu cores detected by Python)

  • temperature (int or float) – Monte Carlo temperature (default: 1), “T” in atat code

  • wr (int or float) – Weight assigned to range of perfect correlation match in objective function (default = 1)

  • wn (int or float) – Multiplicative decrease in weight per additional point in cluster (default: 1)

  • wd (int or float) – Exponent of decay in weight as function of cluster diameter (default: 0.5)

  • tol (int or float) – Tolerance for matching correlations (default: 1e-3)

Returns

Tuple of Pymatgen structure SQS of the input structure, the mcsqs objective function,

list of all SQS structures, and the directory where calculations are run