phonon_lifetime package

An Example project.

class phonon_lifetime.NormalMode

Bases: ABC

Represents a normal mode of the system.

abstract property omega: float

The frequency of the mode.

abstract property system: System

The system that this normal mode belongs to.

abstract property vector: ndarray[tuple[int, int], dtype[complex128]]

The vector of the mode.

class phonon_lifetime.NormalModeResult

Bases: ABC

Result of a normal mode calculation for a phonon system.

get_all_modes() → list[NormalMode]

Get all the normal modes in the calculation.

abstractmethod get_mode(branch: int, q: int | tuple[int, int, int]) → NormalMode

Get the normal mode for a given branch and q point.

abstract property n_branch: int

The number of branches in the calculation.

abstract property n_q: int

The number of q points in the calculation.

class phonon_lifetime.PristineMode(*, _system: System, _omega: float, _primitive_vector: ndarray, _q_val: ndarray)

Bases: NormalMode

A normal mode of a pristine system.

property omega: float

The frequency of the mode.

property primitive_vector: ndarray[tuple[int], dtype[complex128]]

The primitive vector of the mode.

property system: System

The system that this normal mode belongs to.

property vector: ndarray[tuple[int, int], dtype[complex128]]

The vector of the mode.

class phonon_lifetime.PristineNormalModeResult(*, system: System, omega: ndarray[Any, dtype[floating]], modes: ndarray[Any, dtype[floating]], q_vals: ndarray[Any, dtype[floating]])

Bases: NormalModeResult

Result of a normal mode calculation for a phonon system.

get_mode(branch: int, q: int | tuple[int, int, int]) → PristineMode

Get the normal mode for a given branch and q point.

property n_branch: int

The number of branches in the calculation.

property n_q: int

The number of q points in the calculation.

class phonon_lifetime.System(*, element: str, primitive_cell: ndarray[tuple[int, int], dtype[floating]], spring_constant: tuple[float, float, float], n_repeats: tuple[int, int, int] = (1, 1, 1))

Bases: object

Represents a System of atoms.

element: str

property n_atoms: int

Number of atoms in the system.

n_repeats: tuple[int, int, int] = (1, 1, 1)

primitive_cell: ndarray[tuple[int, int], dtype[floating]]

spring_constant: tuple[float, float, float]

property supercell_cell: ndarray[tuple[int, int], dtype[floating]]

Get the supercell lattice vectors.

supercell_cell[i] is the vector (x, y, z) for the i’th lattice vector of the supercell.

class phonon_lifetime.VacancyMode(*, _system: System, _omega: float, _modes: ndarray, _defect: VacancyDefect)

Bases: NormalMode

A normal mode of a system with a vacancy.

property omega: float

The frequency of the mode.

property system: System

The system that this normal mode belongs to.

property vector: ndarray[tuple[int, int], dtype[complex128]]

The vector of the mode.

class phonon_lifetime.VacancyNormalModeResult(*, system: System, omega: ndarray[Any, dtype[floating]], modes: ndarray[Any, dtype[floating]], _defect: VacancyDefect)

Bases: NormalModeResult

Result of a normal mode calculation for a vacancy system.

get_mode(branch: int, q: int | tuple[int, int, int]) → NormalMode

Get the normal mode for a given branch and q point.

property n_branch: int

The number of branches in the calculation.

property n_q: int

The number of q points in the calculation.

Subpackages

• phonon_lifetime.modes package
  • MassDefect
    • MassDefect.defects
  • MassDefectMode
    • MassDefectMode.omega
    • MassDefectMode.system
    • MassDefectMode.vector
  • MassDefectNormalModeResult
    • MassDefectNormalModeResult.get_mode()
    • MassDefectNormalModeResult.modes
    • MassDefectNormalModeResult.n_branch
    • MassDefectNormalModeResult.n_q
    • MassDefectNormalModeResult.omega
    • MassDefectNormalModeResult.system
  • NormalMode
    • NormalMode.omega
    • NormalMode.system
    • NormalMode.vector
  • NormalModeResult
    • NormalModeResult.get_all_modes()
    • NormalModeResult.get_mode()
    • NormalModeResult.n_branch
    • NormalModeResult.n_q
  • PristineMode
    • PristineMode.omega
    • PristineMode.primitive_vector
    • PristineMode.system
    • PristineMode.vector
  • PristineNormalModeResult
    • PristineNormalModeResult.get_mode()
    • PristineNormalModeResult.modes
    • PristineNormalModeResult.n_branch
    • PristineNormalModeResult.n_q
    • PristineNormalModeResult.omega
    • PristineNormalModeResult.q_vals
    • PristineNormalModeResult.system
  • VacancyDefect
    • VacancyDefect.defects
  • VacancyMode
    • VacancyMode.omega
    • VacancyMode.system
    • VacancyMode.vector
  • VacancyNormalModeResult
    • VacancyNormalModeResult.get_mode()
    • VacancyNormalModeResult.modes
    • VacancyNormalModeResult.n_branch
    • VacancyNormalModeResult.n_q
    • VacancyNormalModeResult.omega
    • VacancyNormalModeResult.system
  • animate_mode_1d_x()
  • animate_mode_2d_xy()
  • calculate_normal_modes()
  • plot_1d_dispersion()
  • plot_dispersion_2d_xy()
  • plot_mode_1d_x()
  • plot_mode_2d_xy()

Submodules

phonon_lifetime.system module

class phonon_lifetime.system.System(*, element: str, primitive_cell: ndarray[tuple[int, int], dtype[floating]], spring_constant: tuple[float, float, float], n_repeats: tuple[int, int, int] = (1, 1, 1))

Bases: object

Represents a System of atoms.

element: str

property n_atoms: int

Number of atoms in the system.

n_repeats: tuple[int, int, int] = (1, 1, 1)

primitive_cell: ndarray[tuple[int, int], dtype[floating]]

spring_constant: tuple[float, float, float]

property supercell_cell: ndarray[tuple[int, int], dtype[floating]]

Get the supercell lattice vectors.

supercell_cell[i] is the vector (x, y, z) for the i’th lattice vector of the supercell.

phonon_lifetime.system.get_atom_centres(system: System) → ndarray[tuple[int, int], dtype[floating]]

Get the centres of the atoms in the system.

phonon_lifetime.system.get_scaled_positions(system: System) → ndarray[tuple[int, Literal[3]], dtype[floating]]

Get the scaled positions of the atoms in the system.

This gives the fraction along each of the ith lattice vector of the supercell.