Premium
Optimally convergent determinantal expansion of many‐electron wave functions
Author(s) -
Thephilou A. K.,
March N. H.
Publication year - 1993
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.560460606
Subject(s) - wave function , eigenvalues and eigenvectors , slater determinant , function (biology) , quantum mechanics , electron , particle (ecology) , physics , mathematics , quantum electrodynamics , atomic orbital , evolutionary biology , biology , oceanography , geology
Abstract It is shown that the many‐electron wave function can be expanded optimally in terms of a set of slater determinants that reduces considerbly the number of determinats differing by a single‐particle wave function. The method is based on a variational procedure. The first step of the present method is the Brueckner optimization. The other determinants of the expansion are obtained by successive optimizations performed under additional constraints. The method is illustrated by specifically three‐and four particle example. Finally, it is concluded that the eigenstates of a many‐ particle system can be approximated by states that neglect single‐particle excitations. The Zero‐order approximation of the present scheme is the Hartree–Fock approximation. © 1993 John Wiley & Sons, Inc.