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arXiv · 1011.4343

Energies of the first row atoms from quantum Monte Carlo

Matthew Brown·John Robert Trail·Pablo Lopez Rios·Richard Needs
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Abstract

All-electron variational and diffusion quantum Monte Carlo calculations of the ground state energies of the first row atoms (Li to Ne) are reported. We use trial wavefunctions of four types: single determinant Slater-Jastrow wavefunctions; multi-determinant Slater-Jastrow wavefunctions; single determinant Slater-Jastrow wavefunctions with backflow transformations; multi-determinant Slater-Jastrow wavefunctions with backflow transformations. At the diffusion quantum Monte Carlo level and using our best trial wavefunctions we recover 99% or more of the correlation energy for Li, Be, B, C, N, and Ne, 97% for O, and 98% for F.

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Matthew Brown, John Robert Trail, Pablo Lopez Rios, Richard Needs. 2010-11-19. Energies of the first row atoms from quantum Monte Carlo. https://doi.org/10.1063/1.2743972

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