# MNDO Hamiltonian matrix elements

This directory contains an implementation of the Hamiltonian matrix elements for the
Modified Neglect of Differential Overlap (MNDO) model. The original MNDO model was developed
specifically for s and p orbitals, and was expanded to d orbitals in the 1990's.

The s/p-orbital components were derived and adapted from the original MNDO program, and the
d-orbital components were derived and adapted from the MNDO96 program written by Walter Thiel.

Several subroutines in this directory are attributed to E. R. Davidson, but their origin is unclear.
