Search

The idea that a molecule need not necessarily have a single Kossel Lewis-Langmuir electronic structure, but may be a hybrid of several such, is not new in chemistry, Recently, however, it has been given a much more definite meaning, and has been made amenable to quantititative treatment by the application of wave mechanics to the problem; moreover, it is now realised how extensive the phenomenon is, owing largely to the work of Pauling and his collaborators on energies and internuclear distances. It is the purpose of this paper to show that it is possible, from electric dipole moment data, to decide independently whether or not there is resonance in a molecule, and also to obtain a rough idea of the nature of the more important parent structures and of their relative importance.

When monoenergetic atoms are continuously introduced into a thermal gas, they can undergo deactivating, activating, and reactive collisions. The net result of such collisions is to establish a steady-state distribution of laboratory energies which, although not as sharp as the initial distribution, preserves some of its features, such as being centred at about the initial energy. The reactive collisions which occur under these conditions are characterized by the associated relative energy distribution function and the energy-dependent reaction cross section. As a result, as the initial laboratory energy of the atoms is experimentally varied, the relative energy distribution function can be made to sample appropriately the reaction cross section curve. Therefore, from measurements of the competition between reaction and thermalization processes as a function of initial atom laboratory energies, and from a knowledge of the non-reactive differential scattering cross section, it is possible to obtain information about the dependence on relative energy of the rotationally averaged reaction cross section. The appropriate Boltzmann steady-state equation needed to obtain this information is derived in this paper and solved for an assumed set of reactive and non-reactive cross sections. Distribution functions of relative energies are thereby obtained and used to indicate the usefulness of the suggested measurements.