NMR of 51V in a Heusler alloy Fe2VSi

NMR experiments of 51V are reported for two samples of Fe2VSi: one is quenched after annealing at 1073K and the other is quenched after annealing at 1123 K. Free-decay signals were observed at high temperature and the hyperfine coupling constant is determined to be −5.0 ± 0.5 kOe/μB for both samples, indicating that the vanadium atoms do not carry a moment. The temperature dependence of the width of the field-swept spin-echo spectra at low temperature is consistent with the commensurate and incommensurate anti-ferromagnetic spin structures proposed from neutron experiments. The magnetism in Fe2VSi strongly depends on the degree of atomic order.