Exploration of the formation of XLi3N2 compounds (X = Sc-Zn) by means of density functional theory

Ternary lithium nitrides XLi3N2 are known to form for the 3d transition elements X = Sc, Fe. We explore the formation of such compounds for other 3d elements by means of density functional theory using the crystal structures of ScLi3N2 and FeLi3N2 as templates. Enthalpies of formation, including electronic and phonon contributions, are calculated for the most thermodynamically stable structures. Stability with respect to known binary and ternary compounds is also investigated in order to assess prospects for phase formation. While the X = Ni, Cu, and Zn phases are thermodynamically unstable with respect to metal X, Li3N, and N-2 gas, and thus unlikely to form, our results suggest that the X = Ti, V, Cr, Mn, and Co compounds merit attempts at synthesis. In the case of FeLi3N2, we find an antiferromagnetic configuration lower in energy than the ferromagnetic state previously identified.