%0 Journal Article %1 Scheiring.2000b %A Scheiring, T. %A Kaim, W. %A Olabe, J. A. %A Parise, A. R. %A Fiedler, J. %D 2000 %J Inorganica Chimica Acta %K cyano dinuclear dinuclear;ruthenium electrochem oxidn prepn pyrazine ruthenium %P 125--130 %R 10.1016/S0020-1693(99)00456-9 %T The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad (NC)5M(m-pz)M(CN)55-, M = Fe, Ru, Os; pz = pyrazine %V 300-302 %X The new Ru(II) complex ion (NC)5Ru(m-pz)Ru(CN)56- was prepd. and studied as the hexakis(tetraethylammonium) salt. Although spectroelectrochem. expts. in CH2Cl2 were affected by adsorption as they were in other solvents, the compd. could be oxidized via two reversible 1-electron steps with a mixed-valent pentaanionic intermediate. In comparison with the Fe and Os analogs, the system (NC)5Ru(m-pz)Ru(CN)55- is distinguished by less neg. redox potentials, a smaller comproportionation const. Kc of only 104.7, a very broad (Dn1/2 = 4200 cm-1) sym. IVCT band at 1760 nm (e = 2600 M-1 cm-1) conforming with the Hush model for weakly coupled mixed-valent systems, the absence of an EPR signal even at 3.5 K and the appearance of IR bands (CN, pyrazine ring vibrations) indicating localized valence on the time scale of 10-12 s. Together with the high MLCT energies these results suggest a weaker metal-pyrazine interaction for the Ru system in comparison with the Fe and Os analogs reported previously. In relation to the Creutz-Taube ion, the substitution of ammine ligands by noninnocent cyanide ions attenuates the metal-metal interaction across the p accepting pyrazine bridge. on SciFinder(R)

@article{Scheiring.2000b, abstract = {The new Ru(II) complex ion [(NC)5Ru(\textgreek{m}-pz)Ru(CN)5]6- was prepd. and studied as the hexakis(tetraethylammonium) salt. Although spectroelectrochem. expts. in CH2Cl2 were affected by adsorption as they were in other solvents, the compd. could be oxidized via two reversible 1-electron steps with a mixed-valent pentaanionic intermediate. In comparison with the Fe and Os analogs, the system [(NC)5Ru(\textgreek{m}-pz)Ru(CN)5]5- is distinguished by less neg. redox potentials, a smaller comproportionation const. Kc of only 104.7, a very broad (\textgreek{Dn}1/2 = 4200 cm-1) sym. IVCT band at 1760 nm (\textgreek{e} = 2600 M-1 cm-1) conforming with the Hush model for weakly coupled mixed-valent systems, the absence of an EPR signal even at 3.5 K and the appearance of IR bands (CN, pyrazine ring vibrations) indicating localized valence on the time scale of 10-12 s. Together with the high MLCT energies these results suggest a weaker metal-pyrazine interaction for the Ru system in comparison with the Fe and Os analogs reported previously. In relation to the Creutz-Taube ion, the substitution of ammine ligands by noninnocent cyanide ions attenuates the metal-metal interaction across the \textgreek{p} accepting pyrazine bridge. [on SciFinder(R)]}, added-at = {2022-06-15T11:26:56.000+0200}, author = {Scheiring, T. and Kaim, W. and Olabe, J. A. and Parise, A. R. and Fiedler, J.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2057205a5df311379468ba18aef77f499/huebleriac}, doi = {10.1016/S0020-1693(99)00456-9}, interhash = {febfd33e5eb9579964536340ba6c6d96}, intrahash = {057205a5df311379468ba18aef77f499}, issn = {0020-1693}, journal = {Inorganica Chimica Acta}, keywords = {cyano dinuclear dinuclear;ruthenium electrochem oxidn prepn pyrazine ruthenium}, pages = {125--130}, timestamp = {2022-06-15T09:26:56.000+0200}, title = {The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(\textgreek{m}-pz)M(CN)5]5-, M = Fe, Ru, Os; pz = pyrazine}, volume = {300-302}, year = 2000 }