Crystal structure and physical properties of the new ternary compound MgNi7B3

A new compound MgNi7B3 in the Mg-Ni-B ternary system was prepared by solid state reaction and its crystal structure was determined using X-ray powder diffraction data. The MgNi7B3 compound crystallizes with ErNi7B3 structure type (space group I41/amd, a = 7.4877(2) Å, c = 15.4879(4) Å, Z = 8.), and the Rietveld refinement of the crystal structure was performed which gave Rwp = 7.02%, Rp = 4.96%. The MgNi7B3 sample was characterized by magnetization and electric resistivity measurements. MgNi7B3 exhibits metallic behavior in the temperature range from 5 to 300 K and shows spin-glass-like behavior at low temperature with the spin freezing temperature (Tf) around 13 K.