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arXiv · 2104.00797

Nonlocal pseudopotentials and time-step errors in diffusion Monte Carlo

Tyler A. Anderson·C. J. Umrigar
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Abstract

We present a version of the T-moves approach for treating nonlocal pseudopotentials in diffusion Monte Carlo which has much smaller time-step errors than the existing T-moves approaches, while at the same time preserving desirable features such as the upper-bound property for the energy. In addition, we modify the reweighting factor of the projector used in diffusion Monte Carlo to reduce the time-step error. The latter is applicable not only to pseudopotential calculations but to all-electron calculations as well.

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Tyler A. Anderson, C. J. Umrigar. 2021-07-27. Nonlocal pseudopotentials and time-step errors in diffusion Monte Carlo. https://doi.org/10.1063/5.0052838

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