Methods for calculating forces within quantum Monte Carlo simulations.

نویسندگان

  • A Badinski
  • P D Haynes
  • J R Trail
  • R J Needs
چکیده

Atomic force calculations within the variational and diffusion quantum Monte Carlo methods are described. The advantages of calculating diffusion quantum Monte Carlo forces with the 'pure' rather than the 'mixed' probability distribution are discussed. An accurate and practical method for calculating forces using the pure distribution is presented and tested for the SiH molecule. The statistics of force estimators are explored and violations of the central limit theorem are found in some cases.

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عنوان ژورنال:
  • Journal of physics. Condensed matter : an Institute of Physics journal

دوره 22 7  شماره 

صفحات  -

تاریخ انتشار 2010