Structural, Mechanical, and Electronic Properties of High-Hardness Silicon Tetranitride.

ABSTRACT: Materials with high hardness are critical for industrial and aerospace applications, prompting the search for novel compounds with robust covalent networks. Using a first-principles structure prediction method, we systematically explored the phase stability of Si-N compounds under high pressure. We identified two thermodynamically stable phases: Si₆N with P-1 symmetry and SiN₄ with space group R-3c. Phonon spectra and ab initio molecular dynamics simulations confirm the dynamical and thermal stability of R-3c SiN₄ at ambient pressure and up to 2000 K. Notably, R-3c SiN₄ exhibits exceptional mechanical properties with a Vickers hardness of 31 GPa, a bulk modulus of 259.53 GPa, and a Young's modulus

SUBMITTER: Liu L 

PROVIDER: S-EPMC12654970 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature