Phase Stability and Compressibility of 3R-MoN₂ at High Pressure.

ABSTRACT: We report phase stability and compressibility of rhombohedral 3R-MoN₂, a newly discovered layer-structured dinitride, using in-situ synchrotron high-pressure x-ray diffraction measurements. The obtained bulk modulus for 3R-MoN₂ is 77 (6) GPa, comparable with that of typical transition-metal disulfides (such as MoS₂). The axial compressibility along a axis is more than five times stiffer than that along c axis. Such strong elastic anisotropy is mainly attributed to its layered structure with loosely bonded N-Mo-N sandwich interlayers held by weak Van der Waals force. Upon compression up to ~15 GPa, a new hexagonal phase of 2H-MoN₂ occurs, which is irreversible at ambient conditions. The structural transition mechanism between 3R and 2H phases is t

SUBMITTER: Zhou X 

PROVIDER: S-EPMC6642113 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature