Accurate Studies On The Molecular Dissociation Energies Of Some Diatomic Electronic States

There are five parts in this dissertation. Part one and part two briefly describe the significance, the progress, the physical models and several physical methods used to study the molecular dissociation energies (DE) of diatomic molecular electronic states. Part three introduces the algebraic method (AM) and a parameter-free analytical formula for dissociation energies of diatomic molecular electronic states which is based on the vibrational energy expression given by LeRoy and Bernstein using the WKB quantum condition. The new formula of D_e does not depend on any molecular parameters, and is only the function of the three highest vibrational energies near molecular dissociation limit. In part four, together with AM method the new analytical formula is applied to obtain accurate dissociation energies for some electronic states. The results show that the method of AM and the new analytical formula can get correct full vibrational energy spectrum {E_v} and molecular dissociation energies by solving algebraic equation from a known accurate experimental vibrational energy subset without using any mathematical approximations and physical models. These high-lying vibrational energies may be difficult to obtain using modern experimental methods or accurate quantum theoretical methods. Comparing with other experimental or theoretical methods, the AM is a reliable, economical and valid method to obtain full molecular vibrational spectrum, and the new analytical formula is a hew physical tool to get accurate molecular dissociation energies, particularly for those diatomic electronic systems whose DE are difficult to accurately obtain using modern experimental technique.