English

Reducing the time-step errors in diffusion Monte Carlo

Chemical Physics 2024-03-18 v2

Abstract

We modify the reweighting factor of the projector used in diffusion Monte Carlo to reduce the time-step error of the total energy. Further, we present a reweighting scheme that has the desirable feature that it is exactly size-consistent, i.e, the energy of a system containing widely separated fragments is the same as the sum of the energies of the individual fragments. The practical utility of the latter improvement is that it reduces the time-step error of the binding energies of some weakly interacting systems.

Keywords

Cite

@article{arxiv.2312.01526,
  title  = {Reducing the time-step errors in diffusion Monte Carlo},
  author = {Tyler A. Anderson and Manolo C. Per and C. J. Umrigar},
  journal= {arXiv preprint arXiv:2312.01526},
  year   = {2024}
}

Comments

15 pages, 3 figures; expanded discussion of results, discussion of time-step error for all-electron systems added to supplementary material