Stereochemical effects on intervalence charge transfer
نویسندگان
چکیده
Recent work has revealed the first observation of stereochemical effects on intervalence charge transfer (IVCT) in diand trinuclear mixed-valence complexes. The differential IVCT characteristics of the diastereoisomers of polypyridyl complexes of ruthenium and osmium offer a new and intimate probe of the fundamental factors that govern the extent of electronic delocalization and the barrier to electron transfer. These findings challenge prior assertions that the inherent stereochemical identity of such complexes would have no influence on the intramolecular electron-transfer properties of polymetallic assemblies. This article provides a brief review of the past 40 years of mixed-valence research and looks at recent progress in stereochemical effects on IVCT. The implications of the findings are considered within the context of the existing theoretical and experimental framework for IVCT.
منابع مشابه
Stereochemical influences on intervalence charge transfer in homodinuclear complexes of ruthenium.
The synthesis of polynuclear transition metal assemblies and their electrochemical, photochemical, and photophysical properties have attracted significant recent interest; this has been motivated largely by the potential of multicomponent systems as a basis of novel applicable materials.1 However, the existence of the stereochemical complexities inherent in such systems, and their influence on ...
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The mixed-valence systems meso- and rac-[{M(bpy)2}2(mu-BL)]5+ {M = Ru, Os; BL = a series of polypyridyl bridging ligands such as 2,3-bis(2-pyridyl)benzoquinoxaline (dpb)} are characterized by multiple intervalence charge transfer (IVCT) and interconfigurational (IC) bands in the mid-infrared and near-infrared (NIR) regions. Differences in the relative energies of the IC transitions for the full...
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