electronic structure and properties of silver-magnesium alloys

The electronic structures of beta'-AgMg and Ag3Mg alloys have been investigated by a combination of photoelectron spectroscopy and first-principles band structure and photocurrent calculations. The study includes the first ever XPS and UPS measurements from the ordered and disordered phases of Ag3Mg. We concentrated mainly on measurements of the valence bands and the core level binding energies for these alloys and their parent metals. The band structures of the ordered alloys and pure metals have been calculated by the SCF-LMTO-ASA method, and the KKR and KKRCPA calculational schemes have been used in order to determine the electronic structures of both ordered and disordered phases of Ag3Mg on an equal footing. For the purpose of interpreting the core level shifts due to alloying, a modified LMTO scheme has been applied, in a supercell geometry, to allow for relaxation effects. In addition, we have shown that the Fermi surface topology may well be an important factor in determining the relative stability of the long period superlattice structure in Ag3Mg. In general, the calculations are in very good agreement with the experimental results. We conclude that the combination of theoretical calculations and photoemission measurements provides a detailed understanding of the electronic structures and the properties of Ag-Mg alloys.