Generalization to Many Solutes

In the previous four sections, we discussed the solvent-induced interactions between a pair of solvatons. These could be H0O-H0O, H0I-H( I, or a mixed H0O-H I pair. 

The extension to any number of solvatons is quite straightforward. In this section we discuss some aspects of the solvent-induced interactions among many simple H0O solvatons in water. An extension to more complex molecules is discussed in section 8.9. 

In section 7.15 we presented an approximate measure of the H0O interaction between two methane molecules at a distance of i 1.53 A. We noted also that the distance R 1.53 A is not accessible to real solutes, so that little can be inferred on the H0O interaction at more realistic distances. 

In this section we present a modified measure of the H0O interaction which is based on essentially the same type of arguments as in section 7.15 but can, in principle, provide improved information. The improvement is achieved in both the nature of the approximation and the realizability of the final configuration of the solutes. The extent of the improvement depends on the availability of relevant experimental data. 

As a prototype of our new measure we consider the neopentane molecule. Using the same arguments as in section 7.15, the solvent-induced interaction among five methane molecules brought to the final configuration of a neopentane molecule (see Fig. 7.32) is written as follows  

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