The crystal structure of Hf3As

Hf₃As has a monoclinic unit cell of dimensions a = 15.3898(14) Å, b = 5.3795(5) Å, c = 15.330(14) Å, β = 90.291(6)°. A structure proposal based on space group $\text{C2}\text{c}$ (No. 15) has been refined by the least-squares method using a Rietveld-type fullprofile analysis of Guinier-Hägg X-ray powder film intensity data. The Hf₃As structure is an intermediate between the Fe₃P and the Ti₃P types. The atomic coordination follows rules formulated earlier for representatives of the Fe₃PTi₃PV₃S family of structures.