pymatgen.analysis.energy_models module

class EnergyModel

Bases: monty.json.MSONable

Abstract structure filter class.

classmethod from_dict(d)

get_energy(structure)

Returns a boolean for any structure. Structures that return true are kept in the Transmuter object during filtering.

class EwaldElectrostaticModel(real_space_cut=None, recip_space_cut=None, eta=None, acc_factor=8.0)

Bases: pymatgen.analysis.energy_models.EnergyModel

Wrapper around EwaldSum to calculate the electrostatic energy.

Initializes the model. Args have the same definitions as in pymatgen.analysis.ewald.EwaldSummation.

Parameters:

• real_space_cut (float) – Real space cutoff radius dictating how many terms are used in the real space sum. Defaults to None, which means determine automagically using the formula given in gulp 3.1 documentation.
• recip_space_cut (float) – Reciprocal space cutoff radius. Defaults to None, which means determine automagically using the formula given in gulp 3.1 documentation.
• eta (float) – Screening parameter. Defaults to None, which means determine automatically.
• acc_factor (float) – No. of significant figures each sum is converged to.

as_dict()

get_energy(structure)

class IsingModel(j, max_radius)

Bases: pymatgen.analysis.energy_models.EnergyModel

A very simple Ising model, with r^2 decay.

Parameters:

• j (float) – The interaction parameter. E = J * spin1 * spin2.
• radius (float) – max_radius for the interaction.

as_dict()

get_energy(structure)

class NsitesModel

Bases: pymatgen.analysis.energy_models.EnergyModel

Sets the energy to the number of sites. More sites => higher “energy”. Used to rank structures from smallest number of sites to largest number of sites after enumeration.

as_dict()

get_energy(structure)

class SymmetryModel(symprec=0.1, angle_tolerance=5)

Bases: pymatgen.analysis.energy_models.EnergyModel

Sets the energy to the -ve of the spacegroup number. Higher symmetry => lower “energy”.

Args have same meaning as in pymatgen.symmetry.finder.SpacegroupAnalyzer.

Parameters:

• symprec (float) – Symmetry tolerance. Defaults to 0.1.
• angle_tolerance (float) – Tolerance for angles. Defaults to 5 degrees.

as_dict()

get_energy(structure)