phonon_lifetime.system package

System module.

class phonon_lifetime.system.StrainSystem(cell: C, strain: ndarray[tuple[int, int, Literal[3], Literal[3]], dtype[floating]], strain_repeats: tuple[int, int, int])

Bases: Generic

Represents a system for phonon calculations.

property cell: C

Get the cell of the system.

property strain: ndarray[tuple[int, int, Literal[3], Literal[3]], dtype[floating]]

Get the strain of the system.

property strain_repeats: tuple[int, int, int]

Get the strain repeats of the system.

phonon_lifetime.system.as_supercell(strian_system: StrainSystem, n_repeats: tuple[int, int, int]) → StrainSystem[SuperCell]

Get the strain of the supercell.

phonon_lifetime.system.plot_xy(system: StrainSystem, displacement: ndarray[tuple[int, Literal[3]], dtype[floating]] | None = None, *, ax: Axes3D | None = None, bond_cutoff: float = inf, scale_bond_lines: bool = True) → tuple[Figure, Axes3D, tuple[PathCollection, Line3DCollection]]

phonon_lifetime.system.plot_xyz(system: StrainSystem, displacement: ndarray[tuple[int, Literal[3]], dtype[floating]] | None = None, *, ax: Axes3D | None = None, bond_cutoff: float = inf, scale_bond_lines: bool = True) → tuple[Figure, Axes3D, tuple[PathCollection, Line3DCollection]]

phonon_lifetime.system.with_ase_forces(cell: C, *, periodic: tuple[bool, bool, bool] = (True, True, True), n_repeats: tuple[int, int, int] | None = None) → StrainSystem

Return a new StrainSystem with forces calculated using ASE.

Parameters

cell: C

The system to calculate forces for. The system should be a pristine system, or at least have a well defined primitive cell.

periodic: tuple[bool, bool, bool]

Whether to apply periodic boundary conditions in each direction when calculating forces. This will affect which atoms are considered nearest neighbors.

n_repeats: tuple[int, int, int] | None

The number of repeats to use when calculating forces. If None, will simulate the full system.

phonon_lifetime.system.with_nearest_neighbor_forces(cell: C, spring_constant: float, *, cutoff: float = 2.46, periodic: tuple[bool, bool, bool] = (True, True, True)) → StrainSystem

Return a new PristineSystem with nearest neighbor forces added.

The forces are added in the form of a spring force between nearest neighbor, with the given spring constant. The cutoff is used to determine which atoms are considered nearest neighbor.

phonon_lifetime.system.with_zero_forces(cell: C) → StrainSystem

Return a new StrainSystem with zero forces.