horton_part.mulliken module

Mulliken partitioning

get_mulliken_operators(overlap, ncenter, shell_types, shell_maps)

Return a list of Mulliken operators for the given basis.

Parameters:

  • overlap (np.ndarray, shape=(nbasis, nbasis), dtype=float) – The overlap matrix in a given basis.

  • ncenter (int) – Number of basis centers.

  • shell_types (list) – Sequence of integers representing the basis shell types.

  • shell_maps (list) – Sequence of integers representing the center each shell belongs to.

get_shell_nbasis(shell_type)

Return number of basis functions in the given shell type.

Parameters:

shell_type (int) – Integer representing the shell.

partition_mulliken(operator, nbasis, shell_types, shell_maps, index)

Fill in the mulliken operator in the first argument.

Parameters:

  • operator (np.ndarray, shape=(nbasis, nbasis), dtype=float) – A Two index operator to which the Mulliken mask is applied.

  • nbasis (int) – Number of basis function.

  • shell_types (list) – Sequence of integers representing the basis shell types.

  • shell_maps (list) – Sequence of integers representing the center each shell belongs to.

  • index (int) – The index of the atom (center) for which the Mulliken operator needs to be constructed.

  • the (This routine implies that the first natom centers in the obasis corresponds to) –

  • system. (atoms in the) –