The present monograph appears after the death of Professor V. N. Kondratiev, one of those scientists who have greatly contributed to the foundation of contem porary gas kinetics. The most fundamental idea of chemical kinetics, put for ward at the beginning of the twentieth century and connected with names such as W. Nernst, M. Bodenstein, N. N. Semenov, and C. N. Hinshelwood, was that the complex chemical reactions are in fact a manifestation of a set of simpler elementary reactions involving but a small number of species. V. N. Kondratiev was one of the first to adopt this idea and to start...

The theory of atom-molecule collisions is one of the basic fields in chemi cal physics. Its most challenging part - the dynamics of chemical reactions - is as yet unresolved, but is developing very quickly. It is here a great help to have an analysis of those parts of collision theory which are already complete, a good example being the theory of atomic collisions in process es specific to chemical physics. It has long been observed that many notions of this theory can also be applied successfully to reactive and unreactive molecular collisions. More over, atomic collisions often represent a...