Ma, A. and Towler, M. D. and Drummond, Neil and Needs, R. J. (2005) Scheme for adding electron–nucleus cusps to Gaussian orbitals. Journal of Chemical Physics, 122 (22): 224322. ISSN 1089-7690
Full text not available from this repository.Abstract
A simple scheme is described for introducing the correct cusps at nuclei into orbitals obtained from Gaussian basis set electronic structure calculations. The scheme is tested with all-electron variational quantum Monte Carlo (VMC) and diffusion quantum Monte Carlo (DMC) methods for the Ne atom, the H2 molecule, and 55 molecules from a standard benchmark set. It greatly reduces the variance of the local energy in all cases and slightly improves the variational energy. This scheme yields a general improvement in the efficiency of all-electron VMC and DMC calculations using Gaussian basis sets.