Dissociative electron transfer interactions between fragments

Comparison with the case of a purely repulsive product profile [equation (3.17)] vs. equations (3.3) and (3.4) reveals that the effect of an attractive interaction between the fragments in the product cluster is not merely described by the introduction of a work term in the classical theory of dissociative electron transfer. Such a work term appears under the form of —AG p, but there is also a modification of the intrinsic barrier. With the same Ap, the change in the intrinsic barrier would simply be obtained by replacement of Dr by /Dr — /D )2. It is noteworthy that small values of DP produce rather strong effects of the intrinsic barrier. For example, if DP is 4% of Dr, a decrease of 20% of the intrinsic barrier follows. The fact that a relatively small interaction leads to a substantial decrease of the activation barrier is depicted in Figure 3.4. 

Pause, L., Robert, M. and Savdant, J.-M. (2000) Reductive cleavage of carbon tetrachloride in a polar solvent. An example of a dissociative electron transfer with significant attractive interaction between the caged product fragments. J. Am. Chem. Soc. 122, 9829-9835. 

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