Studies On The Potential Energy Surface And Quantum Dynamics Of He-X₂(X=Na, Li) System

Collisional energy transfer is an important topic in the fields of physics, chemistry, life sciences and material sciences. In this thesis, we have performed systematic studies on quantum dynamics of the He-Na₂ and He-Li₂ system, based on the background of Buffer-gas cooling experiment. It includes the theoretical investigation on the potential energy surfaces and collision dynamics.This paper is divided into four parts. In chapter one, the development of dynamical studies for the He-X₂(X=Na,He) system are briefly introduced. In chapter two, the basic principle of the molecular orbits ab initio and the theory of the inelastic scattering are presented. In chapter three, the potential energy surface for He-Na₂ system has been calculated. The quantum dynamics are introduced in detail. In chapter four, the potential energy surface for He-Li₂ system has been calculated. It also has two potential wells as the potential energy surface for He-Na2. The whole potential energy surface exhibits weak anisotropic. We discussed the similarities and differences between the two complexes. Our main work is presented as following:(1) The intermolecular interaction energies corresponding to different He-Na₂ and He-Li₂ configurations have been calculated by...