Molecular reactants which are anisotropically reactive

Many of the fast chemical reactions discussed in the preceding sections involve at least one reactant which is of low symmetry. The reactions of the solvated electron with nitrate, naphthalene or pyrene are instances where the oxidant has a mirror plane (in the molecular plane) in the accepting orbital. Hence, reaction of the solvated electron with such a scavenger when both are contained in this plane should be slower than in other configurations. Similarly, the contact quenching of fluorescence from naphthalene or 1,2-benzanthracene by carbon tetrabromide [7], or 

The factors which influence the rate of rotational relaxation are briefly discussed in the next two sections. These are then considered in relation to experimental studies of chemical reaction in which rotational effects may be of importance. 

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