An X-ray photoelectron study of valence charge in transition metal aluminides

Abstract In an earlier paper we proposed a new method for interpretation of background structure in X-ray photoelectron (XP) spectra and showed that this could be used to study bonding states in intermetallic compounds using, as an example, a particular Ti—Al alloy. In this paper we have applied this method to study a set of aluminides: Me—Al alloys, where Me represents a transition metal: Ti, V, Fe, Ni or Nb. The method for background interpretation is based on a peak-shape parameter k, which links the intrinsic energy loss structure, associated with a given line in the XP spectrum, to the atomic number. This parameter is thus related to the number of final state configurations available to the photoexcited atom or ion and we show, now, how the value for aluminium varies across a series of compounds with the transition metals. The results for k are accompanied by measurement of the Auger parameters which may be indicative of the charge transfer occurring between Al and Me and thus are also influenced by ...