O+H(D)_(2)^(+)(v=0,1^(2)j=0)在两个不同势能面上的络合物动力学

O+H(D)_(2)(v=0,1^(2)j=0)Complex Dynamics at Two Different Potential Energy Surfaces

本文在基态势能面1^(2)A’’和第一激发态势能面1^(2)A’上研究了氧原子和氢分子离子的碰撞。这两个势能面的最小反应路径上均存在深势阱。本文计算了依赖碰撞能的中间络合物的平均寿命。结果显示在这两个势能面上,中间络合物的平均寿命随着碰撞能的增加而减小。反应存在两种机制,一个是直接反应,另外一个是间接反应。在研究的碰撞能范围内,间接反应占据了主导地位。然而,随着碰撞能的升高,直接反应机制变得越来越重要。另外,本工作还详细研究了反应物激发态和同位素效应对标量性质的影响。尽管反应物振动激发对中间络合物的平均寿命影响很小,但它显著地提高了基态势能面上直接反应的轨线数。相反,在激发态势能面上,反应物振动激发减少了间接反应的轨线数并减小了中间络合物的平均寿命。同位素效应对标量性质没有影响。

In this paper,the collisions between oxygen atoms and hydrogen molecules have been studied on the ground state potential energy surface 1^(2)A"and the first excited state energy surface 1^(2)A".There are deep potential Wells on the minimum reaction paths of the two potential surfaces.The mean lifetime of intermediate complexes dependent on collision energy is calculated.The results show that the mean lifetime of the intermediate complex decreases with increasing collision energy on both potential energy surfaces.There are two kinds of reaction mechanism,one is direct reaction,the other is indirect reaction.In the range of collision energy studied,indirect reaction plays a dominant role.However,with the increase of collision energy,the direct reaction mechanism becomes more and more important.In addition,the effects of excited states and isotope effects on vector and scalar properties of reactants are studied in detail.Although the reactant vibrational excitation has little effect on the mean lifetime of intermediate complexes,it significantly increases the number of orbitals for direct reactions on the ground state potential energy surface.On the contrary,vibrational excitation of reactants reduces the number of indirect reaction orbits and the mean lifetime of intermediate complexes at the excitation energy level.The isotopic effect has a great effect on vector properties,but not on scalar properties.