The preparation and purification method of a new ruthenium(III)-rhodium(III) cluster, [Ru2Rh(u3-0)(u-CH3COO)6(L)3]+(L = H20 or pyridine (py)), are described. The mixed-metal structure was confirmed by the1H and13C NMR spectra (splitting of all the signals to a 1:2 intensity ratio) and the metal 3d electron signal intensities of the X-ray photoelectron spectra. The mixed-metal aqua and pyridine complexes exhibit an intense visible absorption peak at 576 nm (e 2000 M-1cm-1) and 590 (3980), respectively. Three reversible one-electron-redox waves are observed at +1.68, +0.79, and -0.78 V vs the Ag/Ag+electrode for the pyridine complex in CH3CN and are assigned to [Ru2Rh]3+/2+, [Ru2Rh]2+/+, and [Ru2Rh]+/0, respectively. ThelH NMR spectrum of the aqua complex in CD3OD changes slowly as the substitution of CD3OD for the aqua ligands takes place, first-order rate constants being 6.0 X 10-5(per Ru) and 1.2 X 10-4s-1at the ruthenium and the rhodium centers, respectively, at 21 °C.
ASJC Scopus subject areas
- Colloid and Surface Chemistry