New structure of ternary compound ErAlSi

A new structure of ternary compound ErAlSi was found, and has been studied by means of X-ray powder diffraction technique and refined by Rietveld method. The new structure of the alumosilicide ErAlSi has a tetragonal α-ThSi2-type structure, space group I41/amd (No. 141), Z = 4 and the lattice parameters a = 4.2244(1) Å and c = 14.5257(2) Å. The magnetic properties of the tetragonal structure of ErAlSi were also investigated. The experimentally determined magnetic effective paramagnetic moment is μeff = 4.38μB per formula unit (4.38μB per Er atom). The calculated Currie point is θP = −26.9 K.