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arXiv · 0801.2742

Scheme for adding electron-nucleus cusps to Gaussian orbitals

A. Ma·M. D. Towler·N. D. Drummond·R. J. Needs
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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.

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A. Ma, M. D. Towler, N. D. Drummond, R. J. Needs. 2008-01-17. Scheme for adding electron-nucleus cusps to Gaussian orbitals. https://doi.org/10.1063/1.1940588

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