Charge transfer complexes, biological electron donor-acceptor

Before 1990 there were no accurate experimental or theoretical values for the Ea of AGCUT. It was recognized that ionization potentials and electron affinities were important to charge transfer in biological processes, but there were three potential measures of the Ea. These were donor acceptor complex data, reduction potentials, and theoretical calculations, each of which resulted in different measures of the Ea. Much of our work during the past decade has attempted to reconcile these differences. 

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