X-RAY-SPECTRA OF BETA NIAL

The nickel L absorption spectra have been measured in equiatomic NiAl and found to agree well with the one-electron density of states calculated by Connolly and Johnson [J.W.D. Connolly and K.H. Johnson, in Electronic Density of States, edited by L.H., Bennett, Natl. Bur. Stand. Spec. Publ. No. 323 (U.S. GPO, Washington, D.C., 1971), pp. 19-25]. Comparisons with like spectra for nickel metal show an apparent shift of the main LIII edge in NiAl, but a more critical comparison of experimental and theoretical curves shows that the 2p core holes remain equidistant from the Fermi level. This is also confirmed for the 1s core holes by remeasured Ni K spectra. The common practice of locating the Fermi level at the initial inflection point in an absorption edge, therefore, is incorrect for these spectra. Good agreement is found between x-ray K, L, and M absorption spectra and inner-shell emission measurements in NiAl.