RElt
calculates overlap, kinetic integrals for numerical atomic orbitals.
The efficient algorithm calculating the overlap and the kinetic integrals for the numerical atomic orbitals is implemented. The described algorithm exploits the properties of the prolate spheroidal coordinates. The overlap and the kinetic integrals in R^3 are reduced to the integrals over the rectangular domain in R^2, what substantially reduces the complexity of the problem. We prove that the integrand over the rectangular domain is continuous and does not have any slope singularities. For...