Using geometrical optimization and DFT method at the B3LYP/6-31G （d） level, nineteen equilibrium geometries were identified, and three transition states of dissociation reaction of C3O6 clusters were also found. The vibrational frequencies and intrinsic reaction coordinate （IRC） verification at the same level were computed to verify the transitions. And then we calculated the dissociation energies and analyzed the dissociation channels. The computational results show that the dissociation energies of C3O6 isomers relative to three CO2 are between 1.509 × 103 and 10.61 × 10^3 kJ·kg^-1, and the energy barriers of the reactions are 92.857, 131.138 and 185.793 kJ·mol^-1. Both the high dissociation energies and high energy barriers show that C3O6 clusters studied in this paper are stable enough to be used as high-energy-density materials.
A clean and efficient method for the synthesis of bis（indolyl）alkanes with antimony trichloride（SbCl3） as the catalyst under solvent-free grinding conditions is described. This method provides several advantages, such as simple work-up procedure, neutral conditions and high yields.
