Structure and magnetic properties of RFe10V2Nx compounds

In this paper a systematic study is undertaken of the structure and magnetic properties of RFe10V2 nitrides using X-ray diffraction, thermomagnetic analysis, SQUID magnetometry and neutron diffraction. RFe10V2Nx compounds were prepared by heat-treating fine powders of single-phase RFe10V2 alloys in N2 gas. These studies showed that the interstitial nitrogen atoms expand the crystal lattice of ThMn12-type crystal structure, resulting in a substantial increase of Curie temperature. The average increase of Curie temperature across the series is about 200 K. The absorption of nitrogen also introduces a significant change in the magnetocrystalline anisotropy from ''weak uniaxial''-type to ''strong uniaxial''-type for NdFe10V2Nx and from ''uniaxial'' to ''planar'' in SmFe10V2Nx. (orig.)