CH4+O(3P)→CH3+OH反应的准经典轨线研究

用准经典轨线方法研究了O（3P）与CH4的反应，计算结果表明，CH4（υ＝0，j＝0）与O（3P）的反应在低及高的碰撞参数下都是直接反应，无短寿命的碰撞复合物生成，产物OH以向后散射为主，基本上处于振转基态.CH4（υ＝1，j＝1）与O（3P）的反应在低及高的碰撞参数下反应机理不一样。在低碰撞参数下是直接反应，无短寿命的碰撞复合物生成，产物OH以向后散射为主，主要处于振动基态，转动基本上是冷的，但比高碰撞参数下的热.在高的碰撞参数下则生成短寿命的碰撞复合物，产物OH以向前散射为主，表现出明显的周边动力学反应的特征，主要处于振动激发态（υ＝1），但转动仍然是较冷的。

A Quasiclassical Trajectory Study of the CH4+O(3P)→CH3+OH Reaction

The reaction of CH4+O(3P)→CH3+OH was studied with the quasiclassical trajectory calculation. Both CH4(v=0, j=0) and CH4(v=1, j=1) were used. The results showed that the reaction of CH4(v=0, j=0) + O(3P) → CH3+OH is a direct reaction at lower or larger impact parameters with the preferentially backward scattered OH, and the product OH is rotationally cold and in the vibrationally ground state. The reaction of CH4(v=1, j=1) + O(3P)→CH3+ OH is a peripheral dynamical reaction with the preferentially forward scattered OH. This reaction was found to proceed with two distinct mechanism: for trajectories with a large impact parameter, a very short lived complex is formed with a rotationally cold OH, which is in vibrationally excited state(v=1) and scattered into the forward direction; at smaller impact parameters, the reaction proceeds via a direct mechanism with a rotationally hot OH, which has little vibrational excitation and is scatted backward.