pengwann.occupations.fixed

occupations.fixed(eigenvalues, mu)

A simple heaviside occupation function.

Parameters:

eigenvaluesndarray of float

The Kohn-Sham eigenvalues.

mufloat

The Fermi level.

Returns:

occupation_matrixndarray of float

The occupation matrix.

Notes

The definition of this occupation function is simply

\[\begin{split}f_{nk} = \begin{cases} 1\; \mathrm{if}\; \epsilon_{nk} \leq \mu \\ 0\; \mathrm{if}\; \epsilon_{nk} > \mu. \end{cases}\end{split}\]