A DFT study of 1-amino-2,4-dinitroimidazole and its three derivatives

摘要

In this study, density functional theory (DFT) investigation at B3LYP/aug-cc-pVDZ level were performed to explore the geometric and electronic structures, band gaps and heats of formations of the energetic compounds, 1-amino-2,4-dinitroimidazole (R1) and its three derivatives: 1-nitroimidazole-2,4-dinitroimidazole (R2), 1,2,4-trinitroimidazole(R3) and 1,2-bis (2,4-dinitro-1H-imidazol-1-yl)diazene (R4). The detonation properties and densities of these compounds were evaluated by VLW equation and experiential methods, respectively. Results show that these compounds have high densities (1.791 to 1.938 g·cm~(-3) ) and excellent detonation performance (D 8.74 to 9.21 km·s~(-1), P 35.90 to 55.63 GPa). All of them appear to be potential explosives compared with the well known ones, 1,3,5-trinitro-1,3,5-triazine (RDX, 8.75 km·s~(-1), 34.70 GPa) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetraazocane (HMX, 8.96 km·s~(-1), 35.96 GPa), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20, 9.40 km·s~(-1), 42.00 GPa), especially R3 (9.21 km·s~(-1), 55.63 GPa). In addition, different substituted groups determine the heat of formation, stability, sensitivity, density, and detonation performance of these compounds.