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Title: A Blocked Linear Method for Optimizing Large Parameter Sets in Variational Monte Carlo

Abstract

We present a modification to variational Monte Carlo’s linear method optimization scheme that addresses a critical memory bottleneck while maintaining compatibility with both the traditional ground state variational principle and our recently-introduced variational principle for excited states. For wave function ansatzes with tens of thousands of variables, our modification reduces the required memory per parallel process from tens of gigabytes to hundreds of megabytes, making the methodology a much better fit for modern supercomputer architectures in which data communication and per-process memory consumption are primary concerns. We verify the efficacy of the new optimization scheme in small molecule tests involving both the Hilbert space Jastrow antisymmetric geminal power ansatz and real space multi-Slater Jastrow expansions. Satisfied with its performance, we have added the optimizer to the QMCPACK software package, with which we demonstrate on a hydrogen ring a prototype approach for making systematically convergent, non-perturbative predictions of Mott-insulators’ optical band gaps.

Authors:
 [1]; ORCiD logo [2]
  1. Univ. of California, Berkeley, CA (United States)
  2. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1376512
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Chemical Theory and Computation
Additional Journal Information:
Journal Volume: 13; Journal Issue: 6; Journal ID: ISSN 1549-9618
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Zhao, Luning, and Neuscamman, Eric. A Blocked Linear Method for Optimizing Large Parameter Sets in Variational Monte Carlo. United States: N. p., 2017. Web. doi:10.1021/acs.jctc.7b00119.
Zhao, Luning, & Neuscamman, Eric. A Blocked Linear Method for Optimizing Large Parameter Sets in Variational Monte Carlo. United States. doi:10.1021/acs.jctc.7b00119.
Zhao, Luning, and Neuscamman, Eric. 2017. "A Blocked Linear Method for Optimizing Large Parameter Sets in Variational Monte Carlo". United States. doi:10.1021/acs.jctc.7b00119.
@article{osti_1376512,
title = {A Blocked Linear Method for Optimizing Large Parameter Sets in Variational Monte Carlo},
author = {Zhao, Luning and Neuscamman, Eric},
abstractNote = {We present a modification to variational Monte Carlo’s linear method optimization scheme that addresses a critical memory bottleneck while maintaining compatibility with both the traditional ground state variational principle and our recently-introduced variational principle for excited states. For wave function ansatzes with tens of thousands of variables, our modification reduces the required memory per parallel process from tens of gigabytes to hundreds of megabytes, making the methodology a much better fit for modern supercomputer architectures in which data communication and per-process memory consumption are primary concerns. We verify the efficacy of the new optimization scheme in small molecule tests involving both the Hilbert space Jastrow antisymmetric geminal power ansatz and real space multi-Slater Jastrow expansions. Satisfied with its performance, we have added the optimizer to the QMCPACK software package, with which we demonstrate on a hydrogen ring a prototype approach for making systematically convergent, non-perturbative predictions of Mott-insulators’ optical band gaps.},
doi = {10.1021/acs.jctc.7b00119},
journal = {Journal of Chemical Theory and Computation},
number = 6,
volume = 13,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
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