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Linear-scaling quantum Monte Carlo with non-orthogonal localized orbitals

D. Alfe`·M. J. Gillan
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Abstract

We have reformulated the quantum Monte Carlo (QMC) technique so that a large part of the calculation scales linearly with the number of atoms. The reformulation is related to a recent alternative proposal for achieving linear-scaling QMC, based on maximally localized Wannier orbitals (MLWO), but has the advantage of greater simplicity. The technique we propose draws on methods recently developed for linear-scaling density functional theory. We report tests of the new technique on the insulator MgO, and show that its linear-scaling performance is somewhat better than that achieved by the MLWO approach. Implications for the application of QMC to large complex systems are pointed out.

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D. Alfe`, M. J. Gillan. 2004-04-23. Linear-scaling quantum Monte Carlo with non-orthogonal localized orbitals. https://doi.org/10.1088/0953-8984%2F16%2F25%2Fl01

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