Understanding and improving the efficiency of full configuration interaction quantum Monte Carlo.

@article{Vigor2016UnderstandingAI,
  title={Understanding and improving the efficiency of full configuration interaction quantum Monte Carlo.},
  author={W. A. Vigor and James S. Spencer and Michael J. Bearpark and Alex J. W. Thom},
  journal={The Journal of chemical physics},
  year={2016},
  volume={144 9},
  pages={
          094110
        }
}
Within full configuration interaction quantum Monte Carlo, we investigate how the statistical error behaves as a function of the parameters which control the stochastic sampling. We define the inefficiency as a measure of the statistical error per particle sampling the space and per time step and show there is a sizeable parameter regime where this is minimised. We find that this inefficiency increases sublinearly with Hilbert space size and can be reduced by localising the canonical Hartree… 

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