Drummond, Neil and Lopez Rios, P. and Ma, A. and Trail, J. R. and Spink, G. G. and Towler, M. D. and Needs, R. J. (2006) Quantum Monte Carlo study of the Ne atom and the Ne+ ion. Journal of Chemical Physics, 124 (22). ISSN 1089-7690Full text not available from this repository.
We report all-electron and pseudopotential calculations of the ground-state energies of the neutral Ne atom and the Ne+ ion using the variational and diffusion quantum Monte Carlo (DMC) methods. We investigate different levels of Slater-Jastrow trial wave function: (i) using Hartree-Fock orbitals, (ii) using orbitals optimized within a Monte Carlo procedure in the presence of a Jastrow factor, and (iii) including backflow correlations in the wave function. Small reductions in the total energy are obtained by optimizing the orbitals, while more significant reductions are obtained by incorporating backflow correlations. We study the finite-time-step and fixed-node biases in the DMC energy and show that there is a strong tendency for these errors to cancel when the first ionization potential (IP) is calculated. DMC gives highly accurate values for the IP of Ne at all the levels of trial wave function that we have considered.
|Journal or Publication Title:||Journal of Chemical Physics|
|Subjects:||Q Science > QC Physics|
|Departments:||Faculty of Science and Technology > Physics|
|Deposited On:||10 Jul 2012 09:29|
|Last Modified:||03 Nov 2015 16:05|
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