Pressure-stabilized high-energy-density material YN₁₀

Polynitrogen compounds have been intensively studied for potential applications as high energy density materials, especially in energy and military fields. Here, using the swarm intelligence algorithm in combination with first-principles calculations, we systematically explored the variable stoichiometries of yttrium–nitrogen compounds on the nitrogen-rich regime at high pressure, where a new stable phase of YN₁₀ adopting I4/m symmetry was discovered at the pressure of 35 GPa and showed metallic character from the analysis of electronic properties. In YN₁₀, all the nitrogen atoms were sp ²-hybridized in the form of N₅ ring. Furthermore, the gravimetric and volumetric energy densities were estimated to be 3.05 kJ g⁻¹ and 9.27 kJ cm⁻¹ respectively. Particularly, the calculated detonation velocity and pressure of YN₁₀ (12.0 km s⁻¹, 82.7 GPa) was higher than that of TNT (6.9 km s⁻¹, 19.0 GPa) and HMX (9.1 km s⁻¹, 39.3 GPa), making it a potential candidate as a high-energy-density material.