Calculated surface segregation in transition metal alloys

We outline a combination of numerical techniques which recently has been used to calculate heats of solution, surface energies and segregation energies for a large number of metals and alloys. The basic ingredients are density functional theory, a Green's function approach to the one-electron problem formulated within a linear muffin-tin orbitals basis, the coherent potential approximation corrected for charge transfer effects by the screened impurity model, and the atomic sphere approximation corrected for the higher multipoles of the charge density. We discuss the accuracy of the combined numerical technique and present results for the surface segregation of single impurities, the stability of pseudomorphically grown overlayers on Ni, and segregation profiles in Rh75Pt25. (C) 1999 Elsevier Science B.V. All rights reserved.