Density functional-based prediction of the electronic, structural, and vibrational properties of the energetic molecule: octanitrocubane

We have performed density functional calculations on the recently discovere d energetic molecule, octanitrocubane C-8(NO2)(8). We predict a strongly ex othermic dissociation energy and calculate the ionization potentials, elect ron affinities and vibrational spectra. We predict that the isolated molecu le exhibits a symmetry which is higher than that found in the solid. The vi brational density of states shows strong Raman activity at low frequencies and strong IR intensities at high frequencies. We identify a low-energy anh armonic mode which is consistent with the experimentally assumed free torsi onal rotations of the NO2 groups about their respective C-N axes. (C) 2000 Elsevier Science B.V. All rights reserved.