Theoretical Studies on Vibrational Spectra, Detonation Properties and Stabilities of Polynitroadamantanes

摘要

To look for high energy density compounds (HEDCs), sixteen polynitroadamantanes were designed and their properties were studied. The assigned infrared spectra of polynitroadamantanes were obtained at the DFT-B3LYP/6-31G level. The frequencies of symmetry stretching vibration of nitro group for polynitroadamantanes have a bathochromic shift with the number of nitro group. However, the frequencies of asymmetry stretching vibration have a contrary trend. The detonation velocity, pressure and heat of 16 polynitroadamantanes were estimated by the Kamlet-Jacobs formula. The stabilities of polynitroadamantanes were studied by the bond dissociation energy and the energy level difference calculation. The number of the nitro group is in direct proportion to the detonation properties. Conversely, it is in inverse proportion to the stability of polynitroadamantanes. Among the polynitroadamantanes having the same number of nitro group, one which the nitro group links with a methylene group has better properties and is unstable than that the nitro group links with a methylidyne group. Consequently, we should balance the stability with energy and density when a new molecule is designed.