Atomic Orbital Basis Sets for Molecular Interactions

In preparation for computational work with molecular orbitals written as linear combinaions of atomic orbitals, for first and second row atoms, we have developed a general procedure to parametrize linear combinations of Gaussian orbitals. We used a Gaussian transform, and a Gauss-Legendre quadrature, to express hydrogenic orbitals (with the correct long-range dependence for collisions) as contracted Gaussians, for a general case with varying effective -Uarges.