Class III delocalization in a cyanide-bridged trimetallic mixed-valence complex
German E Pieslinger1, Pablo Alborés, Leonardo D Slep
1Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, 3° piso Ciudad Universitaria, C1428EHA, Buenos Aires (Argentina).
Angewandte Chemie (International Ed. in English)
|December 31, 2013
Summary
This study identifies the first cyanide-bridged, trimetallic complex exhibiting Class III mixed-valence behavior. Spectroscopic and computational analyses confirm its delocalized electronic nature, a significant finding in inorganic chemistry.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Spectroscopy
Background:
- Cyanide-bridged metal complexes are crucial in constructing polynuclear systems.
- Understanding mixed-valence species is key to developing advanced electronic materials.
Purpose of the Study:
- To investigate the electronic properties of the trimetallic complex trans-[Ru(dmap)4 {(μ-CN)Ru(py)4 Cl}2 ](3+).
- To determine if this cyanide-bridged system exhibits mixed-valence characteristics.
- To explore the implications of intrinsic bridge asymmetry on electronic delocalization.
Main Methods:
- Near-Infrared (NIR) and Infrared (IR) spectroscopy were employed.
- Time-Dependent Density Functional Theory ((TD)DFT) calculations were performed.
- Analysis focused on spectroscopic signatures indicative of mixed-valence states.
Main Results:
- Spectroscopic data strongly support Class III mixed-valence behavior for the trimetallic ion.
- This represents the first reported instance of Class III behavior in a cyanide-bridged system.
- (TD)DFT calculations accurately predicted the observed spectra and confirmed electronic delocalization.
Conclusions:
- The trimetallic complex trans-[Ru(dmap)4 {(μ-CN)Ru(py)4 Cl}2 ](3+) is a Class III mixed-valence species.
- Tuning fragment energies successfully compensated for cyanide bridge asymmetry.
- This work establishes a new class of mixed-valence compounds with potential applications in molecular electronics.
Keywords:
cyanometalatesdensity functional calculationsmetal-metal interactionsmixed-valence compoundsrutheniumMore Related Videos
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