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Nonlocal pseudopotentials and time-step errors in diffusion Monte Carlo

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 نشر من قبل Tyler Anderson
 تاريخ النشر 2021
  مجال البحث فيزياء
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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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