THE 2-STATE REDUCTION FOR ELECTRON AND HOLE TRANSFER IN BRIDGE-MEDIATED ELECTRON-TRANSFER REACTIONS

We present a unified analysis of the two-state reduction in bridge-mediated electron transfer for both electron and hole transfer. The parameter that characterizes the leading error associated with a two-state reduction is derived in the energy and time domains. A precise definition of the tunnelling energy is given. We also derive analytically the regimes of validity of the two-state reduction and we interpret it in terms of the time evolution of the purely electronic part of the electron-transfer probability.