Abstract
Experimental data on the kinetics of elementary gas-phase reactions undergone by molecules are reviewed. The classification of reactions is discussed on the basis of the structure of activated complexes. Reaction mechanisms of various types are analysed in detail. The activation energy is shown to be determined additively mainly by activated bonds: the presence of substituents, which play no direct part in the reaction, has little effect on the activation energy. An analysis is made of the effect of conjugated and cumulative π-bonds in the activated complex on the activation energy. Conjugation and cumulation substantially lower the potential barrier to reaction. A list of 206 references is included.