Elastic and electronic properties of oxygen and carbon incorporated into Zr3N4 and Hf3 N4

The properties of Zr3N4 and Hf3N4 have been examined with and without large concentrations of O impurities. The changes in elastic properties are consistent with recent experimental observations. Similar calculations are reported for large concentrations of C, with slight differences from the undoped material being found. In both cases the changes in elastic properties are attributed to lengthening of the metal–nitride bond. There are large differences in the electronic energy level structure in the presence of O, with profound changes near the Fermi level.