Quasi-classical Trajectory Studies For Several A+BC Reactions

With development of experimental technology and theoretical method, molecular reactive dynamics has made large progress and the dynamical research has gone deep into state-to-state levels. However, workload will intensely increase with system freedom degrees, and nowadays, this will lead to the calculational difficulty on reaction for strict quantum theory beyond four atoms. Quasi-classical trajectory (QCT) method has been extensively applied to microcosmic reactive dynamics owing to its satisfying results. In this paper, we have studied on several reactions of A+BC system in detail, and obtained some dynamical results. In chapter one, the task and development of chemical dynamics, and the method of microcosmic chemical dynamics are briefly presented. In chapter two, the concept of the QCT method is briefly introduced, and the method of studying the reaction of A+BC system by using the QCT method is presented in detail. In chapter three, Reaction of O (1^D) + H₂(X¹Ã¢Ë†â€˜⁺_g )(ν=0,j=0)→O + OH(ν′,j′) has been calculated based on the analytical potential energy function for OH₂. The distributions of the product and competition of the channels for the reaction are discussed. The relation of relative translational energy with reactive cross section, and the effect of relative translational energy on reaction probability are studied, and the microscopic mechanisms of the reaction are also discussed. It has showed that reactive cross section increases with the collision energy in range of 1kcal/mol to 20kcal/mol, but decreases beyond 20kcal/mol. Reaction probability will increase with the appropriate relative translational energy, but decrease for too high energy. In chapter four, Reaction of O (3^P) +HCl(ν,j) →OH (ν′,j′) +Cl( 2^P) has been studied based on the analytical potential energy function of the O (3^P) + HCl system. It has indicated that there is a demarcation point at 49.37kJ/mol for HCl( ν=0 ,j=0, 1, 2). From 19.25 kJ/mol to 49.37kJ/mol, the cross sections for j=0, 1, 2 have a few differences while it is not similar each other beyond this energy, and the ones almost become a linear increase for j =0 beyond 49.37kJ/mol. For HCl (ν=2 ,j=1,6,9), the distributions on rotational states have been calculated, and the results are compared with experimental data obtained by Zhang and coworkers. In chapter five, Reactions of Cl (2^P_3/2) +H₂ (D₂) have been studied on the BW3 surface. Excitation functions, differential cross sections and angular distributions of HCl and DCl products have been calculated. These results are compared with the results of quasi-classical trajectory calculations, quantum mechanical method and experimental data by M. Alagia and S H Lee.