Comparative theoretical studies of high energetic cyclic nitramines

Density functional theory studies on cyclic nitramines were performed at B3LYP/6‐311G(d,p) level. The crystal structures were obtained by molecular packing calculations. Heats of formation (HOFs) were predicted through designed isodesmic reactions. Results indicate that the value of HOF relates to the number of =N–NO₂ group and aza nitrogen atom and increases with the augment of the number of =N–NO₂ group and aza nitrogen atom for cyclic nitramines. Detonation performance was evaluated by using the Kamlet–Jacobs equations based on the calculated densities and HOFs. All the cyclic nitramines exhibit better detonation performance than 1,3,5‐trinitro‐1,3,5‐triazacyclohexane and 1,3,5,7‐tetranitro‐1,3,5,7‐tetraazacyclooctane. The stability of cyclic nitramines was investigated by the bond dissociation energies. The result shows that the increase of =N?NO₂ group or aza nitrogen atom reduces the stability of the title compounds. These results provide basic information for molecular design of novel high energetic density materials. Copyright © 2013 John Wiley & Sons, Ltd.