The effect of the torsional and stretching vibrations of C2H6 on the H + C2H6 --> H2 + C2H5 reaction.
We present a three-dimensional quantum scattering model to treat reactions of the type H + C2H6 --> H2 + C2H5. The model allows the torsional and the stretching degrees of freedom to be treated explicitly. Zero-point energies of the remaining modes are taken into account in electronic structure calculations. An analytical potential-energy surface was developed from a minimal number of ab initio geometry evaluations using the CCSD(T,full)/cc-pVTZ//MP2(full)/cc-pVTZ level of theory. The reaction is endothermic by 1.5 kcal mol(-1) and exhibits a vibrationally adiabatic barrier of 12.0 kcal mol(-1). The results show that the torsional mode influences reactivity when coupled with the vibrational C-H stretching mode. We also found that ethyl radical products are formed internally excited in the torsional mode.
Kerkeni
Boutheïna
B
Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom. Boutheina.Kerkeni@chem.ok.ac.uk
Clary
David C
DC