Calculation of overlap integrals over Slater-type spinor orbitals of arbitrary half-integral spin using auxiliary functions

Abstract

Analytical relations are derived for two-center overlap integrals over the basis set of 2(2s + 1)-component Slater-type spinor orbitals, which can be used for the solution of generalized Dirac equation, introduced by one of the authors, in the linear combination of atomic orbitals approach, where s = 1/2, 3/2, 5/2,.... These relativistic integrals are reduced to the linear combinations of two-center non-relativistic overlap integrals of scalar Slater-type orbitals. The calculations for non-relativistic overlap integrals are performed with the arbitrary values of quantum numbers, screening constants and the location of orbitals. To obtain more accurate results from the calculations, the well-known auxiliary functions A(n) and B-n are used. It is observed that the computer program carrying out these extended calculations, indeed, works without any restrictions and in all ranges of orbital parameters.