Collisional Energy Transfer Between The High States Of Alkali Molecule And Alkali Atoms

Through the experiment research of the collisional energy transfer between the high-lying state of alkali molecules and the ground state atoms, we get the information in order to ascertain the atom molecule interaction potential energy and energy partition, and to seek new laser working energy levels. By means of the optical-optical double resonance technique the whole high half width of the absorption line in volving nonpredissociation level has been measured so that the total radiation rate of a high-state of the alkali molecules can be obtained. By two step stirring up the alkali atoms, we can measure the collisional transfer rate of the alkali atom in a high excitation state and the rate coefficient in the process of collision Reverse energy pooling. With the different ground state atom densities and the fluorescence intensity ratios of the high excitation state atoms to the high-lying state molecules, we get the collisional energy transfer cross sections between the high-state alkali molecules and the ground-state alkali atoms.Changes of the laser induced population in Rb atomic vapor were monitored by decreasing or increasing the corresponding fluorescence signals. The rate constants for the stimulated emission (i.e., 5D5/2→5P3/2) is 2.0×108s-1. The cross section for the fine-structure changing collision (i.e., 5D5/2→5D3/2) is 6.4×10-14cm2. In the collisional energy transfer process Cs(6P3/2)+(Ne,N2), it is possible that the electronic state merely transfer to the translational energy for Ne. However, in the N2 case, it is important to transfer the electronic state to the vibrational or rotational energy. Using stepwise excitation of the cesium 8S atomic level in Cs vapor, the cross sections for the collisional processes of 6P+5D→6S+nL(nL=9S,5F) have been measured. The cross sections on 9S and 5F of the energy transfer process respectively are 8.7×10-15cm2 and 1.3×10-14cm2. We study the resonance exchange collisions in cesium vapor by the optical-optical double resonance spectroscopy. The rate coefficient of 9.62×10-7cm3s-1 for the resonance exchange collisions has been yielded.