The effect of exchange and correlation on the agreement between APW and LCAO Compton profiles and experiment

Abstract

The formulation of an exchange and correlation correction based on that proposed by Lam and Platzman (1974), to theoretical Compton profiles calculated within the local-density approximation is described. This correction is evaluated for Al, Fe, Cr, Ni and V and compared with the differences between existing APW and LCAO calculations and experiment. Improved agreement between the corrected theoretical data and measured profiles is observed for both models. The APW method is found to be somewhat more successful in the formulation of electron momentum densities for good free-electron and transition-metal elements.