Grand-canonical-ensemble representability problem for the one-electron reduced density matrix

D.R. ALCOBA; R.C. BOCHICCHIO; G.E. MASSACESSI; L. LAIN; A. TORRE

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

American Physical Society

Lugar: New York; Año: 2007 vol. 75 p. 12509 - 12509

1050-2947

We deal with many-electron systems having a noninteger number of electrons, which cannot be described properly by means of pure states or by canonical statistical ensemble states. The study of the one-electron reduced density matrix for these systems raises the problem of its representability in statistical ensembles of grand canonical type. We derive the necessary and sufficient conditions for the representability of the one-electron reduced density matrix of grand-canonical statistical ensembles.