Electron correlation effects on Compton profiles of Cr in the GW approximation

The occupation number densities N(k)s of Cr are evaluated from a first-principle calculation of the spectral function within the GW approximation. The dielectric matrix needed for the screened potential W is calculated within the random-phase approximation. The Compton profiles (CPs) of Cr are calculated using the N(k)s. Anisotropic electron correlation effects in the directional CPs of Cr, which cannot be described within the local density approximation, are successfully reproduced by using the N(k)s. (C) 2001 Elsevier Science Ltd. All rights reserved.