Electron momentum density and Compton profile in disordered alloys

We present a brief overview of the Korringa-Kohn-Rostoker coherent potentia l approximation (KKR-CPA) formalism as it applies to the problem of obtaini ng the average momentum density and Compton profile in a disordered alloy; the electron correlations are treated within the local spin density (LSD) a pproximation. The applicability of such a KKR-CPA-LSD approach to non-magne tic as well as magnetic systems is illustrated by considering several recen t studies which include: Li-rich LiMg, Al-rich AlLi, the cubic perovskites Ba1-xKxBiO3 and BaPbxBi1-xO3, and the Ni-rich NiCu and NiCo magnetic alloys . These examples highlight the interplay between effects of electron correl ations and disorder on the one hand, and between changes in the Fermi surfa ce topology and the onset of various phase transformations on the other. (C ) 2001 Elsevier Science Ltd. All rights reserved.