M. Davies

IMPURITY AUGER-SPECTRA - A PROBE OF THE LOCAL IMPURITY DENSITY OF STATE AND THE IMPURITY ELECTRON ELECTRON INTERACTIONS

We show that the local impurity density of states and the impurity electron—electron interactions can be obtained from impurity Auger spectra. For a Ag0.95Pd0.05 alloy we find 11% Pd(d) character in the Ag d band and Pd(4d-4d) Coulomb interactions which are much larger than the virtual bound state widths.

Pd M4,5N4,5N4,5 Auger spectra of Ag80Pd20 and Cu95Pd5: the influence of the conduction band densities of states

The spectral profiles of Pd M4,5N4,5N4,5 transitions of Ag80Pd20 and Cu95Pd5 are calculated using the Cini-Sawatzky model for a filled band system the multiplet structure obtained from atomic structure calculations and single electron densities of states obtained from the results of SCF-KKR-CPA calculations. Reasonable agreement with experiment is obtained for Ag80Pd20 but not for Cu95Pd5. Agreement with experiment is improved if the calculated intensities of states at the bottom of the band, associated with bonding states, is arbitrarily reduced and the M5N4,5N4,5:M4N4,5N4,5 intensity ratio is modified to take account of the influence of M4M5N4,5 Coster-Kronig transitions.

Calculation of Mg atom-metals XPS and Auger shifts using a ΔSCF excited atom model

The excited atom model using Delta SCF Hartree-Fock calculations is tested on Mg metal. It is found that the valence configurations of the ground, one- and two-core-hole states may be unambiguously determined simply from the values of the atom-metal XPS and Auger shifts. The above state energies suggest 3s13p1, 3s23p1 and 3s23p2 configurations, respectively, in agreement with previously reported band-structure calculations and XES and Auger studies.

An X-ray and ultraviolet photoemission investigation of the density of states of metallic Mg

Conduction band spectra of Mg metal have been obtained using X-ray and UV excitation. The spectra are compared with the conflicting band-structure calculations of Gupta and Freeman (1976) and Citrin et al. (1979). It is shown that the latter yields densities of states in better agreement with experimental observations.

Observation of KL2,3L2,32V satellite Auger transitions in Mg metal

A satellite structure to high energy of the K-L2,3V band spectrum in metallic Mg has been resolved using soft X-ray excitation. The observed energy of the structure is shown to be consistent with that predicted for KL2,3-L2,32V transitions on the basis of excited atom Delta SCF Hartree-Fock calculations. The spectral profile is shown to be adequately reproduced using the K-L2,3V lineshape and the multiplet structure of the initial and final states.