Symmetrical overlap transformations of function basis sets: the LCAO MO and quantum similarity practical cases

Abstract

Quantum chemical computational procedures, like LCAO MO theory and quantum similarity, use non orthogonal function basis sets, which define finite dimensional subspaces of a Hilbert space. Based on the original overlap metric matrices, generated by the chosen finite non orthogonal basis sets, there are several symmetrical overlap and basis set transformations possible. This study tries to find out the general point of view, from where all these procedures can be studied in a clear generalized perspective.