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Title: Weighted nodal domain averages of eigenstates for quantum Monte Carlo and beyond

Journal Article · · Chemical Physics
 [1];  [2]
  1. North Carolina State University, Raleigh, NC (United States); OSTI
  2. North Carolina State University, Raleigh, NC (United States)

In this report we study the nodal properties of many-body eigenstates of stationary Schrödinger equation that affect the accuracy of real-space quantum Monte Carlo calculations. In particular, we introduce weighted nodal domain averages that provide a new probe of nodal surfaces beyond the usual expectations. Particular choices for the weight function reveal, for example, that the difference between two arbitrary fermionic eigenvalues is given by the nodal hypersurface integrals normalized by overlaps with the bosonic ground state of the given Hamiltonian. Noninteracting and fully interacting Be atom with corresponding almost exact and approximate wave functions are used to illustrate several aspects of these concepts. Variational formulations that employ different weights are proposed for prospective improvement of nodes in variational and fixed-node diffusion Monte Carlo calculations.

Research Organization:
North Carolina State University, Raleigh, NC (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0012314
OSTI ID:
1976953
Journal Information:
Chemical Physics, Journal Name: Chemical Physics Journal Issue: C Vol. 557; ISSN 0301-0104
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

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