Internal Energy State Distribution of Product CaBr in the Collision Reactions Ca+C2H5Br和Ca+nC3H7Br

The internal energy distributions of product CaBr in the collision reactions Ca+C2H5Br and Ca+nC3H7Br 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/mol 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+nC3H7Br， 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.