碰撞能对O（~1D）＋HBr→OH＋Br反应的极化分布的影响  

Effects of Collision Energy to Polarization Distribution of O（~1D）＋HBr→OH＋Br Reaction

作　　者：金坤[1] 许雪松[1] 尹淑慧[1] 李磊[1] 

机构地区：[1]大连海事大学物理系

出　　处：《化学学报》2011年第8期919-924,共6页Acta Chimica Sinica

基　　金：辽宁省教育厅高等学校科研计划(No.2009A099);中央高校基本科研业务费专项基金(No.2009JC09);辽宁省博士科研启动基金项目(No.20061047)资助项目

摘　　要：运用准经典轨线法结合Peterson从头计算势能面,在碰撞能分别为20.9,41.80和66.88 kJ/mol时,对放热反应O(1D)+HBr(v=0,j=0)→OH+Br(·H=-252.89 kJ/mol)进行了细致的立体动力学性质研究.反映k与j'两矢量相关的函数P(θr)的分布表明产物分子的转动角动量j'在垂直于反应物相对速度矢量k的方向上有强烈的取向分布,且随碰撞能的变化比较明显;反映k,k'与j'三矢量相关的函数P(φr)的分布表明产物转动角动量j'不仅有沿着y轴的取向效应,还有沿着y轴正向的弱定向效应,且这种弱定向效应随碰撞能的增加有所减弱;描述产物转动角动量j'的空间分布函数P(θr,φr)在(90°,90°)和(90°,270°)两处有两个明显的分布,随着碰撞能的增加,这两个集中分布越来越密集,碰撞能对该分布有一定的影响.产物分子的极化主要集中在垂直于散射面的平面内.除此之外,极化微分反应截面(PDDCSs)给出了反应产物的散射方向.Theoretical studies of the stereodynamics for the exoergic reation O（1D）＋HBr→OH＋Br have been carried out using the quasi-classical trajectory method on the ab initio global potential energy surface at three collision energies（20.90,41.80 and 66.88 kJ/mol）.The distribution P（θr） of angle between k and j＇ shows that the rotational angular momentum polarization of the product molecule is quite strong and sensi-tive to increasing collision energy.The function which reflecting the angle distribution of three vec-tors correlation k-k＇-j＇ indicates that j＇ is not only aligned,but also oriented preferentially along the positive direction of the y-axis.With the increasing collision energy the orientation becomes weaker and weaker.There are two obvious distributions at（90°,90°） and（90°,270°） for the product rotational angular momen-tum,and the two distributions become intensive with the increase of collision energy,so the colli-sion energy plays an important role in the distribution for the title reaction.The two distributions in-dicate that the product molecule is preferentially polarized perpendicular to scattering plane.In addition,the polarization dependent generalized differential cross-sections show the scattering direction of the product.

关 键 词：O(1D)+HBr 准经典轨线方法 矢量相关 立体动力学 

分 类 号：O643.1[理学—物理化学]