English

Accurate, efficient and simple forces with Quantum Monte Carlo methods

Computational Physics 2007-05-23 v2

Abstract

Computation of ionic forces using quantum Monte Carlo methods has long been a challenge. We introduce a simple procedure, based on known properties of physical electronic densities, to make the variance of the Hellmann-Feynman estimator finite. We obtain very accurate geometries for the molecules H2_2, LiH, CH4_4, NH3_3, H2_2O and HF, with a Slater-Jastrow trial wave function. Harmonic frequencies for diatomics are also in good agreement with experiment. An antithetical sampling method is also discussed for additional reduction of the variance.

Keywords

Cite

@article{arxiv.physics/0409087,
  title  = {Accurate, efficient and simple forces with Quantum Monte Carlo methods},
  author = {Simone Chiesa and David Ceperley and Shiwei Zhang},
  journal= {arXiv preprint arXiv:physics/0409087},
  year   = {2007}
}

Comments

4 pages, 4 figures. Minor changes. Accepted for publication on PRL