Density functional theory studies on two novel poly‐nitrogen compounds: N5+N3− and N5+N5−. (2nd September 2020)

• Record Type: Journal Article
• Authors: Xu, Yuangang; Wang, Pengcheng; Lin, Qiuhan; Lu, Ming
• Is Part Of: Journal of physical organic chemistry. Volume 34:Number 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-09-02
• Subjects: DFT -- energetic properties -- high‐energy‐density material -- poly‐nitrogen compounds -- structure; Chemistry, Physical organic -- Periodicals; 547.1
• DOI: 10.1002/poc.4135
• Languages: English
• ISSNs: 0894-3230

Abstract

Abstract: Density functional theory (DFT) methods with B3LYP/6‐311++g(d, p) level of theory were employed to study two poly‐nitrogen salts N5 + N3 − and N5 + N5 − . The optimized geometries and thermochemical parameters, frontier molecular orbitals, molecular electrostatic potential, and predicted infrared (IR) spectra were calculated for inspecting the molecular stabilities, electronic structures, and chemical reactivity. The energetic properties including densities, solid state heats of formation, heats of detonation, detonation velocities, and detonation pressures of N5 + N3 − and N5 + N5 − were also calculated. Results show that the planar N5 + N3 − and N5 + N5 − have higher heats of formation (>1000 kJ mol −1 ) than that of HMX (116.1 kJ mol −1 ) and CL‐20 (365.4 kJ mol −1 ). The detonation velocity of N5 + N3 − is 9.29 km s −1, which is comparable with HMX (9.22 km s −1 ). Especially, N5 + N5 − has a higher detonation velocity (10.21 km s −1 ) than HMX and CL‐20, which means it could be an excellent high‐energy‐density material (HEDM). However, they have a very small energy gap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), which predicts that they have poor stabilities. Abstract : Two poly‐nitrogen salts N5 + N3 − and N5 + N5 − were designed and studied by density functional theory methods. Their optimized geometries and thermochemical parameters, frontier molecular orbitals, molecular electrostatic potential, and predicted IR spectra were calculated for inspecting the molecular stabilities, electronic structures, and chemical reactivity. The calculated energetic properties for N5 + N3 − and N5 + N5 − show that they could be excellent potential HEDMs.