METAL-METAL CHARGE TRANSFER IN LnM-CN-FeCl3 COMPLEXES
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چکیده
By combining the organometallic cyanides L n M-CN [L n M = Cp(dppe)Fe, Cp(dppe)Ru, Cp(PPh 3 ) 2 Ru] with FeCl 3 the dinuclear complexes L n M-CN-FeCl 3 were obtained. Structure determinations have revealed configurations close to linear arrays Fe-C-N-Fe and Ru-CN-Fe. From the n(CN) band positions in their IR spectra it can be concluded that FeCl 3 is a very strong electron acceptor. Accordingly, the redox potentials of the L n M-CN units are raised significantly upon attachment of FeCl 3 . In the visible range of the electronic spectra the complexes show a strong metal-metal charge transfer band, the energy of which is a measure of the electron donating strength of the L n M units. An analysis of the MMCT bands and their solvent dependency resulted in quantitative data on the metal-metal interactions.
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