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Molecular Physics

Operator averages in finite-dimensional N-electron model spaces: a diagrammatic approach

Jacek Karwowski

Published Jun 10, 2004• 0 citations
Publisher

Abstract

An N-electron Hamiltonian projected onto a K-orbital, antisymmetric and spin-adapted model space (in quantum chemistry known as the full configuration interaction space) may be expressed as a linear combination of products of generators of the unitary group . Consequently, spectral density distribution moments and other quantities which characterize global properties of the Hamiltonian spectra in are defined by the averages over the model space of products of the generators. This paper presents a set of new recurrent formulae for the averages and describes a simple graphical method of their evaluation.

DOI
10.1080/00268970410001728708

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