Electron momentum distribution in nickel and copper employing a renormalized free atom model

Abstract

A renormalized free atom (RFA) model has been extended to calculate the momentum density for the angular correlation of positron annihilation radiation (ACPAR). Recent measurements of the Compton profiles (CP) and ACPAR of Ni and Cu have been analysed by the RFA model. It is found that the RFA model gives a good overall description of the CP data for Ni and Cu and for Ni it supports an electronic configuration closer to 3d⁹4s¹. As far as the ACPAR data is concerned, the RFA model does not give an equally satisfactory description of the results. It is suggested that band structure calculations, which give a better agreement with the ACPAR results, are essential to describe positron annihilation data.