碰撞反应Ca+C_2H_5Br和Ca+n-C_3H_7Br产物CaBr的内能态分布  

Internal Energy State Distribution of Product CaBr in the Collision Reactions Ca+C_2H_5Br and Ca+n-C_3H_7Br

作　　者：马建军[1] 丛书林[1] 

机构地区：[1]大连理工大学物理系,大连116024

出　　处：《Chinese Journal of Chemical Physics》2005年第3期319-324,共6页化学物理学报（英文）

基　　金：ProjectsupportedbytheNationalNaturalScienceFoundationofChina(10374012).

摘　　要：采用准经典轨线方法研究了碰撞反应Ca+C2H5Br和Ca+nC3H7Br产物CaBr的内能态分布,计算了产物分子CaBr的平均振动、转动和平动能量以及总可资用能量.结果表明,当碰撞能为7.54kJ/mol时,产物的能量主要为振动能量;随着碰撞能增加,产物的平动能和转动能增加,而振动能略微减小,最可几振动态向较低振动能级移动;反应物分子内能态分布对产物分子的内能态分布影响很小;反应基团越大,产物的振动能占总可资用能量的比例就越高.碰撞反应Ca+C2H5Br和Ca+nC3H7Br均存在两条竞争的反应路径迁移相碰和直接反应路径.前者产生高振动激发态产物CaBr,后者引起C-Br键断裂.当碰撞能增加时,两种反应均倾向于后者.The internal energy distributions of product CaBr in the collision reactions Ca + C2H5Br and Ca + n-C3H7Br are studied by using the quasiclassical trajectory method. The average vibrational, rotational and translational energies and total available energies of the product CaBr molecules are calculated. The results indicate that when the collision energy is equal to 7.54 kJ/moI the energy of product CaBr is mainly the vibrational energy. As the reactant collision energy increases, the average translational and rotational energies of the product CaBr increase, the average vibrational energy decreases slightly, and the most probable vibrational state shifts to lower vibrational energy levels. The internal states of reagents have little influence on the internal energy distribution of the product. The bigger the radical group is, the higher ratio of the vibrational energy to the available energy of the product is. There exist two competitive reaction paths for the collision reactions Ca + C2H5Br and Ca + n-C3H7Br, the migratory encounter and direct reaction paths. The former produces high vibrational excited state product CaBr and the latter causes C-Br bond to break. When the collision energy increases, the reactions tend to the latter path.

关 键 词：准经典轨线 碰撞反应 内能态分布 

分 类 号：O621.13[理学—有机化学]