Photodissociation of carbonyl cyanide CO(CN)2. An ab initio calculation study

The energy, geometry and vibrational frequencies of the parent molecule, products and transition state species (TS) involved in the photochemical decay of carbonyl cyanide NC–C(O)–CN have been studied by ab initio calculations. The planar TS I (110 kcal/mol) along the molecular elimination path to CO+NCCN and the nonplanar TS II (51.6 kcal/mol) along the isomerization path to NC–C(O)–NC have been identified. The theoretical results are found to be consistent with recent experimental findings obtained by photofragment translational energy spectroscopy.