Elastic and electronic properties of CoFe3N, RhFe3N, and IrFe3N from first principles

First principles calculations are performed to investigate the elastic and electronic properties of MFe3N (M=Co,Rh,Ir) at Pm-3m space group. The authors' calculation indicates that the three MFe3N phases are metallic and mechanically stable. For RhFe3N, the calculated lattice parameter of 3.826 A is in excellent agreement with the experimental value of 3.8292 A. The three phases are ferromagnetic with the calculated magnetic moments per f.u. being 8.92 mu(B) for CoFe3N, 9.04 mu(B) for RhFe3N, and 8.50 mu(B) for IrFe3N. The unusually large B/G ratio from 2.47 for CoFe3N and 2.45 for RhFe3N to 1.81 for IrFe3N indicates that they are ductile.