EXPERIMENTAL-STUDY AND THEORETICAL-STUDY OF ANGLE-RESOLVED PHOTOEMISSION SPECTRA FROM THE (111)SURFACE OF ORDERED CUAUI

We report an experimental and theoretical study of angle-resolved phot oemission from the (1 1 1) surface of the ordered alloy CuAuI (L1(0)) structure. The aim of the work is to test the predictions of first-pri nciple band structure calculations by examining the fine details of th e electronic structure as probed by photoemission. We compare theory w ith the experimental measurements not by determining an 'experimental' band structure, but rather by calculating theoretical photocurrent sp ectra using site potential functions determined from first-principle e lectronic structure calculations. We show that the one-particle theory is sufficient to explain the origin of the most important features in the experimental spectra.