First-principle calculation of spin polarization in Cu3N2

We have studied intercalation of nitrogen atom into the cubic Cu3N structure by performing accurate total energy calculations in the framework of density functional theory by using the full-potential linearized augmented plane wave method. The spin polarized Perdew–Burke–Ernzerhof (PBE) and modified Becke–Johnson (mBJ) parameterizations of the generalized gradient approximation were employed to obtain the structural and electronic properties of Cu3N and Cu3N2 structures. It is found that nitrogen intercalation into Cu3N is an endothermic process which significantly influences the structural, electronic, and magnetic properties of the system. This process, within PBE, gives rise to a nearly half metallic behavior, while mBJ favors semiconductor ferromagnetism in the intercalated Cu3N2 system. The 2p orbital of the intercalated nitrogen atom shows significant contribution to the spin polarization of the system. •Cu3N2 structure is thermodynamically stable in an anti-ReO3 type cell.•The compound is half metal with an indirect band gap of 2.5eV and 0.2eV for spin up and spin down states, respectively.•2p orbitals of N intercalated atoms show significant contribution to the system polarization.•The net magnetic moment in ground state is 2.30μB/cell.