Abstract
Zirconium nitride holds promise for improving nuclear reactor components, where thermal conductivity is important, highlighting the need for a detailed understanding of its phonons. However, the phonon dispersion derived from previous inelastic neutron scattering data is in disagreement with modern theoretical calculations, pointing to the necessity for further experimental validation. Here, we use inelastic neutron scattering experiments on polycrystalline ZrN at 6, 100, 300, 400, and 600 K, and density functional theory (DFT) calculations to study the momentum-resolved scattering and the phonon density of states. Both experimental and theoretical results reveal a phonon cutoff energy near 65 meV, in stark disagreement with previous single-crystal neutron scattering measurements indicating a cutoff near 75 meV. The 65 meV cutoff energy is, however, in reasonable agreement with previous measurements on ZrN0.9. Consistency between our theoretical and experimental results confirms that ZrN is a wide phonon band gap system and that DFT provides a reliable description of its phonons.
| Original language | English |
|---|---|
| Article number | 184316 |
| Journal | Physical Review B |
| Volume | 111 |
| Issue number | 18 |
| DOIs | |
| State | Published - May 1 2025 |
Funding
The inelastic neutron scattering measurements by S.W. and M.E.M., sample preparation by J.M.M. and D.B.T., and first-principles calculations by M.A.M. and C.A.M. were supported by the Center for Thermal Energy Transport under Irradiation, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences. The work on data analysis and projection factors by R.P.H. was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Material Science and Engineering Division. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Research conducted at ORNL's Spallation Neutron Source under IPTS–33687 was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy.