ELECTRONIC-STRUCTURE OF NI3TI

The electronic structure of the intermetallic compound Ni3Ti was investigated theoretically with self-consistent-field (SCF)-X± calculations on the appropriate four-atom tetrahedral cluster. The calculations show a d band consisting of filled Ni d orbitals, empty Ti d orbitals, and half-filled Ni-Ti antibonding orbitals near the Fermi level. We obtain from the calculations a charge transfer from Ti to Ni and to the interatomic space so that ionic and covalent components are added to the metallic bond. The energy distributions of photoelectrons from the polycrystalline compound Ni3Ti were obtained at h1/2=11.7, 16.8, 21.2, 26.8, and 40.8 eV and reproduce the features of the calculated electronic structure, namely, a relatively low density of states at the Fermi level and a bandwidth of 3 eV. The Auger peaks of nickel and titanium were obtained at the same energies as for the elemental metals and are in agreement with the theoretical finding that the core levels in the compound are at the same energies as in the elements. © 1979 The American Physical Society.