ELECTRIC-FIELD GRADIENT IN DILUTE V-BASED ALLOYS

Electric-field gradients (EFG's), due to substitutional transition-metal impurities in vanadium have been evaluated using a discrete-lattice static method. The valence and size EFG's are generated simultaneously with the help of perfect and imperfect crystal potentials. The EFG's at the first- and second-nearest neighbors (1NN, 2NN) of the impurity are calculated for the dilute alloys VNb, VMo, VTa, and VW. The d-band effects of both the host and impurity are included through the crystal potential. The calculated results are in agreement with the experimental values. The valence EFG is larger than the size EFG at the 1NN while the size EFG starts dominating at the 2NN sites.