Molecular beam scattering experiments and the determination of intermolecular potentials

The elastic scattering, which will be discussed here, has been most extensively studied. The elastic cross sections show a number of inteference effects, since the intermolecular potential consists of both attractive and repulsive forces. All these interferences, which are most pronounced in the thermal energy range and which contain detailed information on the various regions of the intermolecular potential, have been observed now. The exact quantum mechanical treatment of the elastic scattering is well known and numerical techniques for deriving potentials from the measured scattering data are well developed. Experimental methods along with techniques for the evaluation of intermolecular potentials from measurements of total and differential scattering cross sections are summarized in the following section II. A brief survey of the present status of systems studied is given in section III. Examples of important results are described in section IV. Finally, in section V, I illustrate probable trends of future molecular beam work by means of some recently obtained preliminary results