Effect of antisymmetric C–H stretching excitation on the dynamics of O(1D) + CH4 → OH + CH3

The effect of antisymmetric C–H stretching excitation of CH4 on the dynamics and reactivity of the O(1D) + CH4 → OH + CD3 reaction at the collision energy of 6.10 kcal/mol has been investigated using the crossed-beam and time-sliced velocity map imaging techniques. The antisymmetric C–H stretching mode excited CH4 molecule was prepared by direct infrared excitation. From the measured images of the CH3 products with the infrared laser on and off, the product translational energy and angular distributions were derived for both the ground and vibrationally excited reactions. Experimental results show that the vibrational energy of the antisymmetric stretching excited CH4 reagent is channeled exclusively into the vibrational energy of the OH co-products and, hence, the OH products from the excited-state reaction are about one vibrational quantum hotter than those from the ground-state reaction, and the product angular distributions are barely affected by the vibrational excitation of the CH4 reagent. The reac...