Charge intervalence

Wang C, Mohney B K, Williams R, Hupp J T and Walker G C 1998 Solvent control of vibronic coupling upon intervalence charge transfer excitation of (NC)gFeCNRu(NH3)g- as revealed by resonance Raman and near-infrared absorption spectroscopies J. Am. Chem. Soc. 120 5848-9... 

The mixed-valence ion has an intervalence charge transfer band at 1562nm not present in the spectra of the +4 and +6 ions. Similar ions have been isolated with other bridging ligands, the choice of which has a big effect on the position and intensity of the charge-transfer band (e.g. L = bipy, 830 nm). 

Intervalence Charge Transfer Emd Electron Exchange Studies of Dinuclear Ruthenium Complexes Robert J. Crutchley... 

D Alessandro DM, Keene FR (2006) Current trends and future challenges in the experimental, theoretical and computational analysis of intervalence charge transfer (IVCT) transitions. Chem Soc Rev 35 424 140... 

All compounds were measured at room temperature in air between Au electrodes inside a Faraday cage. IVT = maximum of the optical InterValence Transfer or intramolecular charge transfer band. RR Rectification Ratio. Survives cycling means RR does not decrease with cycling of IV measurements. AR or anti-AR indicates whether electron flow is from A to D (AR) or from D to A (anti-AR)... 

Mixed-valence chemistry was reviewed in the late 1960 s both by Robin and Day (4) and by Hush (5). Their work provided the beginnings of a theoretical background for understanding the properties of mixed-valence compounds including the low energy absorption bands which have been termed Intervalence Transfer (IT) or Metal-Metal Charge Transfer (MMCT) bands. 

The effects of temperature on the shape of intervalence charge-transfer bands for the radical cations of bis(2-f-butyl-2,3-diazabicyclo[2.2.2]oct-3-yl)hydrazines that are bridged by 2,5-xylene-1,4-diyl, durene-l,4-diyl, naphthalene-1,4-diyl, biphenyl-4,4-diyl and 9,9-dimethylfluorene-2,7-diyl aromatic rings were studied by ESR. ... 

Lloveras et al. (2005) compared intervalence electron transfer in l,4-diferrocenyl-l,3-butadiene, [Fc—CH=CH—CH=CH—Fc] andin l,4-diferrocenyl-2-aza-l,3-butadiene, [Fc—CH=N— CH=CH—Fc]. Although intervalence electron transfer in [Fc—CH=CH—CH=CH—Fc] and [Fc—CH=CH—Fc] resemble each other, this process in [Fc—CH=N—CH=CH—Fc] is restricted to some degree. As the authors noted, the population of the state with the positive charge located on the iron attached to the 4-position of the 2-aza-l,3-butadiene bridge is dominant, with just a very small population (<0.1%) of the state with the charge on the other iron site (Lloveras et al. 2005). 

Metal-metal interactions in [(C5H5)(dppe)Fe—CN—Ni(cyclam)— NC—Fe(dppe)(C5H5)] + and [(OC)5Cr—CN—Fe(cyclam)—NC—Cr(CO)5]" were probed by electrochemical and spectroscopic techniques,and intervalence charge-transfer (IVCT) within [(NC)5Fe"CNPt (NH3)5] and [(NC)5Fe"CNPt NCFe(CN)5] analyzed. ... 

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