Orthonormalizations of the Slater-type atom orbitals n from 6 to 7 using the Gramm-Schmidt method

Abstract

Many approximate methods have been developed in molecular orbital theory. The most widely used of these theoretical methods is the Hatree-Fock-Roothaan (HFR) coherent field approach. Appropriate atomic orbitals must be selected for calculations in this approach. There are two types of atomic orbitals commonly used: Slater-type orbitals (STO) and Gaussian-type orbitals (GTO). In this study, STOs were investigated. As is known, STOs are not orthogonal to the principal quantum numbers, which poses some difficulties in electronic structure calculations. Orthogonal and orthonormal Slater-type orbitals were formed for principal quantum numbers larger than known STOs using the Gramm-Schmidt method.