quemb.molbe.pfrag.union_of_frag_MOs_and_index

quemb.molbe.pfrag.union_of_frag_MOs_and_index(Fobjs, S, epsilon=1e-10)

Get the union of all fragment MOs as one Matrix and the respective indices for each fragment to refer to the global fragment MO matrix.

This allows to reuse information such as integrals for the fragment MOs.

Parameters:

• Fobjs (Sequence[Frags]) – A sequence of Frags.

• S (ndarray[tuple[int, ...], dtype[float64]]) – The AO overlap matrix.

• epsilon (float) – Cutoff to consider overlap values to be zero or one.

Return type:

tuple[ndarray[tuple[int, ...], dtype[float64]], list[ndarray[tuple[int], dtype[int64]]]]