Prediction of Caged Polyaza Polynitroamine (Tetracyclo-HMX) as Energetic Compound

By fusing four HMX rings into a cage, a powerful nitroamine explosive was predicted. The heat of formation (HOF) of hetero pentacyclo-icosane nitro compound of dodecanitrododecaza-pentacyclo[9.5.1.13,9. 15,15. 17,13]icosane (DNDAPI or, alternatively, tetracyclo-HMX) was obtained by using density functional theory B3LYP method with 6-31G∗ basis set. The isodesmic reactions designed for the evaluation of HOF keep most of the basic ring structures of the title compounds and thus ensure the credibility of the result. The value of HOF is 1394.59 kJ/mol. The predicted detonation velocity of the title compound is 10.6 km/s and detonation pressure is 56.8 GPa, even at 90% of its theoretical density. These values are much larger than those of the widely used 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX), indicating that DNDAPI is a promising candidate of high energy material. The dissociation energy for the N-NO2 bond in the cage skeleton of the title compound is 125.36 kJ/mol.