Electronic direct “through-space

In order to estimate the intensity and width of the absorption band, we postulate that intensity arises from only direct through-space electron transfer, and estimate the transition moment for this process. The initial state i) of the electron is a totally symmetric linear combination of the three metal t g orbitals, and we represent this simply as an iron 3s Slater orbital whose exponent is taken to be that of the iron 3d orbitals as adopted by Zemer (59, 60), 2.6 au. Using the analogy between the solvated electron and a F ion (19), we represent the final state of the electron f using a fluorine 2s Slater orbital, whose exponent 60, 61) is also 2.6 au. The one-electron matrix element coupling these two states is given in semi-empirical theories 61) as... 

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