Electron dynamics, local control theory

Second, we note that the dynamical aspect of the dielectric response is still incomplete in the above treatment, since (1) no information was provided about the dielectric response frequency and (2) a harmonic oscillator model for the local dielectric response is oversimplified and a damped oscillator may provide a more complete description. These dynamical aspects are not important in equilibrium considerations such as our transition-state-theory level treatment, but become so in other limits such as solvent-control electron-transfer reactions discussed in Section 16.6. 

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