Chemical Physics Letters, Vol.385, No.3-4, 231-232, 2004
Idempotent density matrix derived from a local potential V(r) in terms of HOMO and LUMO properties
In a recent paper one of us has exposed a link between the idempotent Dirac density matrix built from occupied Kohn-Sham orbitals and the frontier orbitals. An alternative argument is here presented, from the equation of motion of the density matrix generated by any local potential V(r). (C) 2004 Elsevier B.V. All rights reserved.