Open Access Nano Idea

Essentially exact ground-state calculations by superpositions of nonorthogonal Slater determinants

Hidekazu Goto*, Masashi Kojo, Akira Sasaki and Kikuji Hirose

Author affiliations

Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan

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Citation and License

Nanoscale Research Letters 2013, 8:200  doi:10.1186/1556-276X-8-200

Published: 1 May 2013

Abstract

An essentially exact ground-state calculation algorithm for few-electron systems based on superposition of nonorthogonal Slater determinants (SDs) is described, and its convergence properties to ground states are examined. A linear combination of SDs is adopted as many-electron wave functions, and all one-electron wave functions are updated by employing linearly independent multiple correction vectors on the basis of the variational principle. The improvement of the convergence performance to the ground state given by the multi-direction search is shown through comparisons with the conventional steepest descent method. The accuracy and applicability of the proposed scheme are also demonstrated by calculations of the potential energy curves of few-electron molecular systems, compared with the conventional quantum chemistry calculation techniques.

Keywords:
Ground-state calculation; Nonorthogonal Slater determinants; Superposition; Few-electron system; Multiple correction vector