Molecular design and performance prediction of poly-dinitroamino pyrrole compounds as energetic materials

Abstract

To identify superior and safe energetic materials, eighteen poly-dinitroamino pyrrole derivatives were studied at the B3LYP/6-311G** level of density functional theory (DFT). The isodesmic reactions were employed to calculate the heats of formation (HOFs) for these compounds. The detonation velocity (D) and pressure (P) were evaluated using the Kamlet-Jacobs equations. Results indicate that –N(NO2)2 group is an effective substituent for enhancing the detonation performance since most of the molecules have larger energy density than RDX (1,3,5-trinitro-1,3,5-triazinane), and a few molecules, C1(N-R) - D3(N-R), with D ranging from 8.55 to 9.04 km s−1 and P ranging from 35.53 to 40.36 GPa outperform RDX (D= 8.75 km s−1 and P= 34.00 GPa). The calculated bond dissociation energy (BDE) revealed that the new compounds exhibit good thermal stability and meet the requirements of energetic materials. Besides, the N-NO2 bond on the side chain was found to be the trigger bond during decomposition. The characteristic height (h 50) of the compound was calculated, and thirteen compounds exhibited lower sensitivity than CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane). To identify superior and safe energetic materials, eighteen poly-dinitroamino pyrrole derivatives were studied at the B3LYP/6-311G** level of density functional theory (DFT). One of the compounds, C2(N-R), is the most promising energetic compound due to its superior energetic properties (D=9.04 km/s, P= 40.36 GPa) and lower sensitivity among all poly-dinitroamino pyrrole derivatives.