Superexchange Charge Transfer in Molecular Wires

Now upon establishing the theoretical framework for the description of molecular-wire behavior, we should analyze the transport phenomena as a function of molecular-wire properties. Firstly, we will discuss the superexchange mechanism. The latter is considered as the main mechanism for efficient electron-transfer within the photosynthetic reaction center [37, 38] and has been studied in various biomimetic systems [39, 40]. 

In superexchange CT reactions, no charge ever actually resides on the bridge. Those states that the molecule occupies between the time when the electron leaves the donor and arrives at the acceptor are called virtual excitations. The transmission probability of electrons to reach the acceptor in this manner is the superexchange 

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