Electronic structure of nickel base alloys: period effect

The authors study the electronic structure of noble and transitional metals in nickel and discuss the effect of the difference, between the impurity and the matrix, of the stability and spatial extension of the atomic 'd' orbitals. Using a realistic band the authors perform the self-consistent calculation of the potential and of the electronic density variations on the impurity site and its nearest neighbours. In the NiCu, NiZn and NiGa alloys it is shown that practically all the 'd' holes are pushed away from the impurity site; in the nickel-based alloys of first series transitional metals, the screening extension on the impurity neighbours is studied. Thus, by studying the stability of various self-consistent solutions, it is shown that the virtual bound states appear more easily if the 'd' orbitals are less stable and more extended