High d-band occupancy in alloys of Mg with some 4d and 5d transition metals: a photoemission study

Abstract

Photoemission data from m-sputtered films of binaly alloys of Ru. Rh, Pd. Ir, Pt and Au with Mg show that the transition meal (m) d band narrow as the TM concentration is reduced, reaching a minimum after which the intensity decreases but the widlh remains constant. The continuity of binding energy, spin-orbit splitling and width of lhe resulting d states suggests a high level of d-band occupanq in all cases. m bandsmcrure calculations for pure TM and ordered intermetallic compounds of the form Mgm and Mg?m also show narrowing of the d bands, with binding energies and widths which indicate thal lhey are fully, or nearly fully occupied in all cases where the TM is dilute. We suggest that the additional d intensity mulls From a spread of the TM d wavefunctions on to the surrounding Mg sites, allowing high d-band occupancy whilst preserving charge neutrality.