Comparison of electron binding energies in Ni3Al, Al, and Ni determined by X-ray photoelectron spectroscopy and quantum-mechanical calculation

Abstract

The electron binding energies of the Al 2 s, Al 2p, Ni 3 s, and Ni 3p levels in Ni3Al intermetallic compound and in pure aluminum and nickel are studied by X-ray photoelectron spectroscopy and quantum-mechanical calculation. It is shown that in Ni3Al the binding energies of the Al 2 s and Al 2p levels are lower by 0.6 eV compared with the reference aluminum, whereas the nickel levels do not shift within the experimental accuracy. The relative changes in the binding energy are confirmed by quantum-mechanical calculations. A more significant chemical shift in the spectra of Al 2 s and Al 2p is caused by a considerable change in the local environment of aluminum atoms in Ni3Al. Thus, quantum mechanical calculations can be used to predict chemical shifts of the electron core levels in intermetallic compounds.