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An efficient method for the Quantum Monte Carlo evaluation of the static density-response function of a many-electron system

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 نشر من قبل Ren\\'e Gaudoin
 تاريخ النشر 2009
  مجال البحث فيزياء
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In a recent Letter we introduced Hellmann-Feynman operator sampling in diffusion Monte Carlo calculations. Here we derive, by evaluating the second derivative of the total energy, an efficient method for the calculation of the static density-response function of a many-electron system. Our analysis of the effect of the nodes suggests that correlation is described correctly and we find that the effect of the nodes can be dealt with.

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