Magnetic Properties of Transition-metal Nitrides

The structural stability of transition-metal nitrides (TMN's) and their magnetic properties in different phases are investigated using first-principles calculations. The early TMN, ScN-CrN, are found to have rocksalt as equilibrium structure at ambient pressure while the later ones (MnN, FeN, and CoN) prefer zincblende. However, the early ones can also adopt the zincblende structure under tensile strain. The tendency towards magnetism is stronger in the rocksalt phase than in the zincblende phase. Antiferromagnetic versus ferromagnetic ordering in the different phases and the relevance of the results to TM-doped GaN are discussed.