Outer-sphere charge transfer

Vogler, A., Kunkeley, H. Photochemistry of Transition Metal Complexes Induced by Outer-Sphere Charge Transfer Excitation. 158, 1-30 (1990). 

The ML species may interact with a species in its second coordination sphere. Therefore one distinguishes inner-sphere charge-transfer and outer-sphere charge-transfer states. 

After an extensive review of MMCT transitions involving ions in solids, it seems wise to start this paragraph with some molecular species, because many of these have been investigated in much more detail than their counterparts in non-molecular solids. It is suitable to make a distinction between outer-sphere charge-transfer (OSCT) and inner-sphere charge-transfer (ISCT) transitions [1], In the former the metal ions do not have ligands in common, in the latter they are connected by a common ligand. Studies are usually performed on metal-ion pairs in solution. 

Vogler A, Kunkeley H (1990) Photochemistry of Transition Metal Complexes Induced by Outer-Sphere Charge Transfer Excitation. 158 1 - 30 Volkert WAJurisson S (1996) Technetium-99m Chelates as Radiopharmaceuticals. 176 123-148 Vondenhof M, see Mattay J (1991) 159 219-255 VoyerN (1997) The Development of Peptide Nanostructures. 184 1-38 Waldmann H, see Sauerbrei B (1997) 186 65 - 86 Walter C.see FessnerW-D (1997) 184 97-194 Wan P, see Krogh E (1990) 156 93-116... 

Photochemistry of Transition Metal Complexes Induced by Outer-Sphere Charge Transfer Excitation... 

Vogler A, Kunkely H. Outer-sphere charge transfer in ion pairs with hydridic, carbani-onic, sulfidic and peroxidic anions as electron donors - spectroscopy and photochemistry. Coord Chem Rev 2002 229 147-52. 

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