DOS

sisl.physics.phonon.DOS(E, hw, distribution='gaussian')

Calculate the density of modes (DOS) for a set of energies, E, with a distribution function

The $\mathrm{DOS}(E)$ is calculated as:

$$\mathrm{DOS}(E)=\sum _{i}D(E-\hslash {\omega }_i)\approx \delta (E-\hslash {\omega }_i)$$

where $D(\mathrm{\Delta }E)$ is the distribution function used. Note that the distribution function used may be a user-defined function. Alternatively a distribution function may be retrieved from distribution.

Parameters:

• E (ndarray) – energies to calculate the DOS at

• hw (ndarray) – phonon eigenvalues

• distribution (Literal['gaussian', 'lorentzian', 'fermi', 'bose-einstein', 'cold', 'step-function', 'heaviside'] | ~typing.Callable[[~collections.abc.Buffer | ~numpy._typing._array_like._SupportsArray[~numpy.dtype[~typing.Any]] | ~numpy._typing._nested_sequence._NestedSequence[~numpy._typing._array_like._SupportsArray[~numpy.dtype[~typing.Any]]] | bool | int | float | complex | str | bytes | ~numpy._typing._nested_sequence._NestedSequence[bool | int | float | complex | str | bytes]], ~numpy.ndarray]) – a function that accepts $E$ as argument and calculates the distribution function.

See also

Distribution functions

a selected set of implemented distribution functions

PDOS

projected DOS (same as this, but projected onto each direction)

Returns:

DOS calculated at energies, has same length as E

Return type:

numpy.ndarray

Parameters:

distribution (Literal['gaussian', 'lorentzian', 'fermi', 'bose-einstein', 'cold', 'step-function', 'heaviside'] | ~typing.Callable[[~collections.abc.Buffer | ~numpy._typing._array_like._SupportsArray[~numpy.dtype[~typing.Any]] | ~numpy._typing._nested_sequence._NestedSequence[~numpy._typing._array_like._SupportsArray[~numpy.dtype[~typing.Any]]] | bool | int | float | complex | str | bytes | ~numpy._typing._nested_sequence._NestedSequence[bool | int | float | complex | str | bytes]], ~numpy.ndarray])