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Nitroamine explosives are a common kind of energetic materials with-NO2. Due to their merit, such as higher energy, excellent comprehensive, wide variety of sourcesand mature manufacturing technology, they are used more and more widely in different areasIn the theory of molecular energetic materials research, the stability has been an important issue in the study of energetic materials, lots of research methods have been proposed.This article studies on the crystal structure of five chain energetic molecular MNA,MDN,DMNA,EDNA and OCPX at 6-311G level with the B3LYP method, and obtain the inner information of molecule, such as their bond length, bond angle, covalent bonds, net charge, Mulliken populations on bonds, total energy and forefront of the energy gap. At the same time, study the common energetic materials TATB,analyzes their influence of stability and reciprocity so as to get some methods to the research on their performance.In five chain energetic molecules, the angle of C-N-N bond’s descending order is MNA(116.8°),MDN(116.5°),DMNA(117.1°),EDNA(122.1°),OCPX(122.9°),the angle of three methylamine is close, the angle of ethylamine is close. The stability has a trend of the increase with the main chain in the five chain energetic molecules. Positive and negative charge arranged in order in five chain molecules. It is obviously reflected in the C-N-N-0 chain, the phenomena of molecule alternating positive and negative is conducive to the stability of the molecular. Mulliken populations of N-N has the least value among the five chain energetic molecules MNA,MDN,DMNA,EDNA and OCPX, Their bond energy are smaller than the C-N bond, N-N bond, N-0 bond and the C-H bonds. We can see that the N-N bond plays a decisive role on the thermal sensitivity of molecular namely pyrolysis among the five chain energetic molecules. The five chain molecules have low energy gap relatively,MNA has the largest energy gap, MDN has the least energy gap, the stability of OCPX, EDNA, DMNA, MDN, MNA decreased in the order.The TATB molecule obtained through optimization calculations is a high molecular symmetry, C-N bond of TATB molecules play a decisive role on the structure and properties, Compared with the five chain energetic molecules, TATB molecules have better stability. The net charge on TATB molecules arranged positive and negative alternately, this is caused by induced polarization of oxygen, the phenomena of molecule alternating positive and negative is conducive to the stability of TATB. Compared with the five chain energetic molecules, TATB has lager energy and the energy gap, it proves the conclusions that TATB energetic materials has higher energy, higher stability.
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