Chemical Physics Letters, Vol.417, No.4-6, 521-523, 2006
Characterization of N-representable n-particle densities when N is infinite
We have found necessary and sufficient conditions for the n-particle density to be N-representable for infinite A, if n is even. There are some mild restrictions on the one-density for these conditions to apply. The method is based on the Mercer expansion theorem. We suggest a simple method for total energy calculations based on this characterization also if the number of particles is finite. (c) 2005 Elsevier B.V. All rights reserved.