Third neighbour hyperfine field shift in a diluteNiAl alloy

In the binary Ni98.5Al1.5 alloy we observed well resolved satellite hyperfine fields at111Cd nuclear probes. The hyperfine shifts derivated are −4.0(3); −8.5(3) and 14.0(3)% relative to the pure nickel value. From the relative intensity of the four components as well as from the quadrupole interaction data we identify the satellites as impurity-probe configurations containing zero, one, two or three Al impurities in the third neighbour shell only. The third neighbour contribution to the hyperfine field at Cd in nickel equals ΔH3= +4.5kG/μB-atom, allowing an estimate ΔH1≃ −17.8 kG/μB-atom for the first shell contribution, confirmed by a similar experiment on Ni98.5Pd1.5.