Novel High-Energy Density Materials. Synthesis and Characterization of Triazidocarbenium Dinitramide, -Perchlorate, and -Tetrafluoroborate

The triazidocarbenium cation, C(N 3 ) 3 +, was successfully combined with the energetic N(NO 2 ) 2 - and ClO 4 - anions in the form of highly energetic salts. The new C(N 3 ) 3 + BF 4 - salt was also prepared, and all compounds were characterized by their material balances and vibrational spectroscopy. Electronic structure calculations were carried out for C(N 3 ) 3 + at the B3LYP/6-31G*, B3LYP/cc-pVDZ, B3LYP/cc-pVTZ, and HF/cc-pVDZ levels of theory. At all levels, the energy minimum is the planar C 3 h structure, and the vibrational spectra were assigned and analyzed for this structure. The heats of formation of C(N 3 ) 3 + N(NO 2 ) 2 - and C(N 3 ) 3 + ClO 4 - were estimated to be endothermic by 252 and 218 kcal mol - 1 and explain the high explosive power of these salts.