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Journal of Physics A Mathematical and General

Form of first-order density matrix for jellium near to the diagonal

Norman Henry March

Published Nov 1, 1975• 6 citations
Publisher

Abstract

Kimball's work (1975) on the momentum distribution of electrons is utilized to establish the form of the expansion of the first-order density matrix for jellium around the diagonal. There is non-analytic behaviour and the connection between the present result and the analytic form for non-interacting electrons in established.
DOI
10.1088/0305-4470/8/11/004

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In a recent paper A. Akbari, N. H. March, and A. Rubio [Phys. Rev. A 76, 032510 (2007)] investigated the one-electron reduced density matrix and the momentum density of several two-electron model atoms, including Hooke's atom. The method used by the authors for deriving an integral form of the momentum density is in fact the most suited for deriving a closed-form expression of the exact reciprocal form factor, in a special case. This function is important inasmuch as it reflects the off-diagonal side of the exact reduced density matrix.
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