Reduced dimensionality quantum reactive scattering: H2+CN→H+HCN

We apply a recently developed, reduced dimensionality quantum theory of diatom–diatom reactive scattering [Q. Sun and J. M. Bowman, Int. J. Quantum Chem., Symp. 23, 115 (1989] to the exoergic H2+CN→H+HCN reaction, for zero total angular momentum. A new semiempirical, three‐dimensional potential surface, which is based in part on ab initio calculations of the saddle point properties is also reported. Reaction probabilities for the ground and first excited bending states of HCN are calculated for total energies up to 1.0 and 1.06 eV, respectively. The results show a strong preference for formation of HCN (0vb1) and HCN (0vb2), vb=0 and 1, starting with ground vibrational state reactants. Reaction probabilities for vibrational excitation of H2 or CN are also reported for both bending states of HCN. Vibrational excitation of H2 is found to be far more effective in promoting reaction than vibrational excitation of CN.

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