Tuning of Metal–Metal Interactions in Mixed-Valence States of Cyclometalated Dinuclear Ruthenium and Osmium Complexes Bearing Tetrapyridylpyrazine or -benzene

The unsymmetrical dinuclear rutheniumiron complexes [(NH3)5RubtaFe(CN)5]n (where bta = benzotriazolate; n = 2, 1, 0) were prepared as solid sodium salts from [RuII(NH3)5(bta)]+ or [RuIII(NH3)5(bta)]2+ and [FeII(CN)5(H2O)]3 and characterized in aqueous solution by means of electrochemical and spectroelectrochemical methods. UV-vis, near-infrared, IR, and cyclic and differential pulse voltammetry data suggest that the related mixed valent species belong to a valence trapped formulation, featuring localized Ru(III) and Fe(II) oxidation states. In spite of the class II categorization in the Robin and Day scheme, this system shows a remarkable metalmetal electronic coupling, as deduced from an intense, low-energy, and very broad intervalence band in the near-IR region. In addition, the mixed valence state displays enhanced stabilization in relation to the isovalent state. The intervalence transfer properties are discussed on the basis of Hush's theory.Key words: ammineruthenium complexes, cyanoiron complexes, mixed valence, intervalence, benzotriazole, benzotriazolate.

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Metal–metal interactions in dinuclear ruthenium complexes incorporating “stepped-parallel” bridging ligands: synthesis, stereochemistry and intervalence charge transfer

New Journal of Chemistry ◽

10.1039/b514111g ◽

2006 ◽

Vol 30 (2) ◽

pp. 228 ◽

Cited By ~ 14

Author(s):

Deanna M. D’Alessandro ◽

F. Richard Keene

Keyword(s):

Charge Transfer ◽

Ruthenium Complexes ◽

Bridging Ligands ◽

Metal Interactions ◽

Metal Metal ◽

Intervalence Charge Transfer ◽

Dinuclear Ruthenium ◽

Dinuclear Ruthenium Complexes

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Highly coupled mixed-valence dinuclear ruthenium and osmium complexes with a bis-cyclometalating terpyridine analog as bridging ligand

Inorganic Chemistry ◽

10.1021/ic00073a012 ◽

1993 ◽

Vol 32 (21) ◽

pp. 4539-4543 ◽

Cited By ~ 86

Author(s):

Marc Beley ◽

Jean Paul Collin ◽

Jean Pierre Sauvage

Keyword(s):

Mixed Valence ◽

Bridging Ligand ◽

Dinuclear Ruthenium ◽

Osmium Complexes

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Linear Chain Bis(α,β-dionedioximato)metal Compounds of the Nickel Triad: Solid State Design by Molecular Engineering

Zeitschrift für Naturforschung B ◽

10.1515/znb-1977-0508 ◽

1977 ◽

Vol 32 (5) ◽

pp. 516-527 ◽

Cited By ~ 33

Author(s):

H. Endres ◽

H. J. Keller ◽

R. Lehmann ◽

A. Poveda ◽

H. H. Rupp ◽

...

Keyword(s):

Solid State ◽

Linear Chain ◽

Mixed Valence ◽

Structural Data ◽

Molecular Engineering ◽

Complex Molecules ◽

Metal Compounds ◽

Metal Interactions ◽

Wide Range ◽

Metal Metal

Chemical and structural data of numerous bis(α,β-dionedioximato)metal(II) compounds are summarized. All of them crystallize in columns but principally two different kinds of molecular arrangements occur in the solids. In one phase the molecular planes are inclined to the direction of the linear metal chains with an angle different from 90°. This allows only indirect interactions between the metal ions via the ligand. (“M—L—M” stacking.) The other modification consists of molecules with their planes perpendicular to the M—M-chains. This form allows direct metal-metal contacts (“M—M” modification). Depending on a few molecular parameters a “M—L—M” or a “M—M” stacking is obtained upon crystallization. Since for those compounds which could be isolated in both modifications the M—L—M form has the higher density it is concluded that only stronger M—M interactions stabilize the less dense M—M forms.A wide range of metal-metal separations with a lower limit of 3.15 Å in mixed valence systems are found in different “M—M” compounds. In any case the intrachain metal-metal distances are reduced considerably upon oxidation of the bivalent complex molecules. The influence of “electronic” and “sterical” parameters of the complex molecules on the intermolecular metal interactions and on the type of columns in the solid state is discussed.

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