Decorrelation of samples in quantum Monte Carlo calculations and scaling of autocorrelation time in Li and H₂O clusters

D. Nissenbaum, Northeastern University
B. Barbiellini, Northeastern University
A. Bansil, Northeastern University

Article comments

Originally posted at http://arxiv.org/abs/0705.2553v1. Preprint of an article published in Physical Review B, v.76 no.3, 2007.

Abstract

We have investigated decorrelation of samples in Quantum Monte Carlo (QMC) ground-state energy calculations for large Li and H₂O nanoclusters. Binning data as a way of eliminating statistical correlations, as is the common practice, is found to become increasingly impractical as the system size grows. We demonstrate nevertheless that it is possible to perform accurate energy calculations—without decorrelating samples—by exploiting the scaling of the integrated autocorrelation time τ as a function of the number of electrons in the system.