Influence of vanadium on the 57Fe-site spin and charge densities in cobalt-vanadium alloys

The influence of substitutional vanadium on spin and charge densities has been studied for a series of hcp Co100√/sub x/V/sub x/ alloys with x≤12.5, using 57Fe-site Moessbauer spectroscopy. It has been shown that one V atom residing in the first-neighbor shell reduces the 57Fe-site hyperfine field by ΔH1 = 38.4 kOe and the isomer shift by ΔI1 = 0.020 mms which means an increase of the charge density by ΔN1/sup s/ = 0.01 s electrons. The influence of one V atom as a second-nearest neighbor is similar in sign but three times smaller in magnitude. The maximum change of the charge density (i.e., that due to three V atoms per unit cell) which can be evaluated from the correlation between the average hyperfine field and the average isomer shift amounts to eta = 0.03--0.05 s electrons. The results are compared with those obtained for the bcc Fe-V system