Relationship between the Marcus prefactor and the electron coupling

For an activationless process we have

(1)

We can estimate the electronic coupling from the measured electron transfer rate constant.. For example, if , then we can rearrange the expression to find

(2)

We note that we would prefer to use units of cm-1 so we will divide the right hand side by hc.

(3)

Using values from the text we can calculate

(4)

Taking the square root we obtain the estimate

(5)

Figure 1 Depiction of the overlap of electron wave functions that leads to electronic coupling.