Theoretical study of the reaction mechanism for the carbon dichlorine radical with isocyanic acid

The reaction mechanism of singlet and triplet CCl₂ with HNCO has been investigated by B3LYP method of density function theory. The geometries and harmonic of reactants, intermediates, transition states and products have been calculated at the B3LYP/6-311++G^** level. Intermediates and transition states were confirmed by the results of vibration analysis and the IRC calculation. The energies of stationary point were calculated at G3 level. The results indicate that the reaction of singlet CCl₂ with HNCO have O-atom abstraction channel, insert N-H channel, NH abstraction channel, and triplet CCl₂ with HNCO has H-atom abstraction channel, among which singlet reaction HNCO+CCl₂→IM₃→TS2→P2 (c₂Cl₂ONH) was the main pathway with the lowest activation energy. (authors)