Neutron and X-ray powder diffraction study on the compound NdFe10.75V1.25Ny

The structural changes that occur in the compound NdFe10.75V1.25 due to nitrogenation have been investigated by neutron and X-ray powder diffraction. Nitrogen occupies less than 60% of the interstitial 2b site, even if the nominal nitrogen content in the structure is 2.4 N atoms/formula unit. The extra nitrogen is believed to occupy other interstitial positions. V occupies preferentially the 8i site in the non-nitrided case. However, this occupancy decreases with increasing nitrogen content. The diffraction data show a strongly anisotropic behaviour of the profile parameters with nitrogen absorption due to the formation of anisotropic strain rather than stacking faults. (orig.)