Crystal and Electronic Structure of UTe-Type Tungsten Nitride Synthesized under High Pressure.

Tungsten nitride continues to drive fundamental interests because of its potential as a functional compound, which combines features such as high hardness together with thermal, chemical, and wear resistance. Here, we report a novel tungsten nitride phase synthesized from MoC-type WN and molecular nitrogen after laser irradiation at = 70 GPa in a diamond anvil cell. This novel phase is quenchable at ambient pressure and determined to be UTe-type tungsten nitride and crystallizes in the hexagonal space group (6) having lattice parameters of = 8.2398(3) Å, = 2.94948(14) Å, and = 173.423(13) Å. Tungsten atoms are coordinated to eight and nine nitrogen atoms, higher than previously reported tungsten nitrides. The bulk modulus is determined to be = 312 (5) GPa ( = 4.0 fixed), and DFT calculations predict that UTe-type WN has a metallic nature.