Spin Structure and Properties of the Correlation Matrices Corresponding to Pure Spin States: Controlling the S-representability of These Matrices

D.R. ALCOBA; C. VALDEMORO

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY

Wiley Periodicals, Inc.

Lugar: New Jersey; Año: 2005 vol. 102 p. 629 - 644

0020-7608

In this paper we investigate the S-representability conditions that a two-body correlation matrix must satisfy when the N-electron system is in a given pure spin state. To purify a trial two-body correlation matrix, the N- and S-representability conditions are combined in a computational procedure for singlet states. This procedure is tested in two calculations on a molecular system and the results are discussed.