Floating shifts of s-type Gaussian type orbitals optimized in molecule’s local environments

Abstract

Abstract For each atom of a molecule, we introduce the structure unit group (SUG) consisted of the atom (called as core-atom) and the neighbor atoms. The kinds of SUG are sampled from small molecules, and the s-type Gaussian type orbitals (GTOs) only for core- and hydrogen atoms of each SUG are floated in the SUG environment. The sampled SUG-floating shifts can be used in the Hartree-Fock calculations of organic molecules. It can make lower some milli-hartree in molecular energy and cause the change of several percent in functional properties such as electric multi-pole moment.