Occupation functions (pengwann.occupations)

Occupation functions for reconstructing the ab initio occupation matrix.

This module contains a set of simple functions for calculating orbital occupation numbers from a set of Kohn-Sham eigenvalues. Any of these functions can be used together with the get_occupation_matrix() function to build the occupation matrix needed to calculated WOBIs with the DescriptorCalculator class.

Functions

get_occupation_matrix(eigenvalues, mu, nspin)	Reconstruct the occupation matrix from an ab-initio calculation.
fixed(eigenvalues, mu)	A simple heaviside occupation function.
fermi_dirac(eigenvalues, mu, sigma)	The Fermi-Dirac occupation function.
gaussian(eigenvalues, mu, sigma)	A Gaussian occupation function.
cold(eigenvalues, mu, sigma)	The Marzari-Vanderbilt (cold) occupation function.