The triazidocarbenium cation, C(N-3)(3)(+), was successfully combined with the energetic N(NO2?)(2)(-) and ClO4- anions in the form of highly energetic salts. The new C(N-3)(3)+BF4- 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-3h structure, and the vibrational spectra were assigned and analyzed for this structure. The heats of formation of C(N-3)(3)N+(NO2)(2)(-) and C(N-3)(3)+ClO4- were estimated to be endothermic by 252 and 218 kcal mol(-1) and explain the high explosive power of these salts.