6533b823fe1ef96bd127f485

RESEARCH PRODUCT

Localization vs. Delocalization in Molecules and Clusters: Electronic and Vibronic Interactions in Mixed Valence Systems

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The interplay between electron delocalization and magnetic interactions play a key role in areas as diverse as solid state chemistry (bulk magnetic materials, superconductors,...) [1] and biology (iron-sulfur proteins, manganese-oxo clusters ...) [2]. In molecular inorganic chemistry these two electronic processes have been traditionally studied independently. Thus, the electron dynamics has been extensively investigated in mixedvalence dimers [3] as exemplified by the Creutz-Taube complex [(NH3)5RuII(pyrazine)RuIII(NH3)5]. In this kind of molecular complexes one extra electron is delocalized over two diamagnetic metal sites. Therefore, they constitute model systems for the study of the electron transfer. Furthermore, their simplicity allowed also to treat at the molecular scale the coupling of electronic and nuclear movements (vibronic interactions), which is an inherent problem for the MV systems since the itinerant electron produces a strong deformation of the coordination sphere of the metal site [4]. The vibronic theory of MV dimers has been formulated by Piepho, Krausz and Schatz and referred to as PKS model [5].