Journal of Physics A Mathematical and General

The first two moments of energy level distributions in N-electron spin-adapted model spaces

Jacek Karwowski, M. Bancewicz

Published Dec 21, 1987• 31 citations

Abstract

Formulae are derived for the average value and for the dispersion of the spectrum of an electronic Hamiltonian in a finite-dimensional, antisymmetric and spin-adapted space. Both the moments are expressed in terms of the corresponding two-electron quantities. The derivation is based on the theory of spin-adapted reduced Hamiltonians.

DOI: 10.1088/0305-4470/20/18/031

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