Crystal structure and high-pressure properties of γ-Mo2N determined by neutron powder diffraction and X-ray diffraction

We prepared samples of cubic γ-MoNx (x  ∼0.5) by high-pressure–high-temperature synthesis. N atom site occupancies within the defect rock salt structure were determined from time-of-flight neutron diffraction and powder X-ray diffraction data by Rietveld analysis. The results show that N atoms occupy only octahedral sites within the structure. The semi-metallic compound is a superconductor, with Tc=5.2K determined by SQUID magnetometry. The compressibility of the material was determined by synchrotron X-ray diffraction measurements at high pressure in the diamond anvil cell. The vibrational density of states was studied by Raman scattering spectroscopy.

The neutron observed (+), calculated (−) and difference profiles (bottom trace) for γ-MoN at 290 K.Figure optionsDownload as PowerPoint slide