Communication: Experimental and theoretical investigations of the effects of the reactant bending excitations in the F+CHD3 reaction

The effects of the reactant bending excitations in the F+CHD3 reaction are investigated by crossed molecular beam experiments and quasiclassical trajectory (QCT) calculations using a high-quality ab initio potential energy surface. The collision energy (Ec) dependence of the cross sections of the F+CHD3(vb=0,1) reactions for the correlated product pairs HF(v′)+CD3(v2=0,1) and DF(v′)+CHD2(v4=0,1) is obtained. Both experiment and theory show that the bending excitation activates the reaction at low Ec and begins to inactivate at higher Ec. The experimental F+CHD3(vb=1) excitation functions display surprising peak features, especially for the HF(v′=3)+CD3(v2=0,1) channels, indicating reactive resonances (quantum effects), which cannot be captured by quasiclassical calculations. The reactant state-specific QCT calculations predict that the v5(e) bending mode excitation is the most efficient to drive the reaction and the v6(e) and v5(e) modes enhance the DF and HF channels, respectively.