PHOTOEMISSION AND ULTRAVIOLET INVERSE-PHOTOEMISSION STUDIES OF CRSE WITH NIAS-TYPE CRYSTAL-STRUCTURE

Valence-band and conduction-band electronic structures of NiAs-type Cr Se have been investigated by means of resonant photoemission, ultravio let photoemission and inverse-photoemission spectroscopies. Based on t he comparison with the results of band-theory, features at -1.5 eV and 1.6 eV relative to the valence-band maximum are assigned to emission from occupied Cr 3d up arrow and unoccupied Cr 3d down arrow states wi th nearly localized character. The energy separation between two peaks provides the Cr 3d spin-exchage splitting energy of 3.1+/-0.2 eV, in relatively good agreement with result of the band-structure calculatio n.