Dynamics of the O(1D) +D2 reaction:: a comparison between crossed molecular beam experiments and quasiclassical trajectory calculations on the lowest three potential energy surfaces

This paper describes crossed beam experiments and quasiclassical trajectory (QCT) calculations for the 'insertion' reaction O(D-1)+D-2 at a collision energy (E-c = 25.9 kJ mol(-1)) much higher than the calculated barrier (similar to 8.4 kJ mol(-1)) for the competitive 'abstraction' mechanism, which takes place along the excited state potential energy surfaces ( PES). Adiabatic QCT calculations were carried out on the ground 1(1)A ' and first excited 1(1)A '' PESs developed by Dobbyn and Knowles. Non-adiabatic contributions from the excited 2(1)A ' PES to the reaction were considered by means of a trajectory surface hopping method. QCT calculations were also performed at E-c = 22.2 kJ mol(-1) to compare with previous experimental results. Excellent agreement was found between experiment and QCT predictions at E-c = 22.2 kJ mol(-1), while at the higher E-c of 25.9 kJ mol(-1) only a qualitative agreement was noted. In all cases, the comparison was significantly improved with respect to QCT calculations on a previous version of the ground state PES.