| Summary: | The reaction between the 2,2’-benzene-1,4-diylbis(6-hydroxy-4,7-di-<i>tert</i>-butyl-1,3-benzodithiol-2-ylium-5-olate triad (<b>H<sub>2</sub>SQ</b>) and the metallo-precursor [Yb(hfac)<sub>3</sub>]⋅2H<sub>2</sub>O led to the formation of a dinuclear coordination complex of formula [Yb<sub>2</sub>(hfac)<sub>6</sub>(<b>H<sub>2</sub>SQ</b>)]⋅0.5CH<sub>2</sub>Cl<sub>2</sub> (<b>H<sub>2</sub>SQ-Yb</b>). After chemical oxidation of <b>H<sub>2</sub>SQ</b> in 2,2’-cyclohexa-2,5-diene-1,4-diylidenebis(4,7-di-<i>tert</i>-butyl-1,3-benzodithiole-5,6-dione (<b>Q</b>), the latter triad reacted with the [Yb(hfac)<sub>3</sub>]⋅2H<sub>2</sub>O precursor to give the dinuclear complex of formula [Yb<sub>2</sub>(hfac)<sub>6</sub>(<b>Q</b>)] (<b>Q-Yb</b>). Both dinuclear compounds have been characterized by X-ray diffraction, DFT optimized structure and electronic absorption spectra. They behaved as field-induced Single-Molecule Magnets (SMMs) nevertheless the chemical oxidation of the semiquinone to quinone moieties accelerated by a factor of five the relaxation time of the magnetization of <b>Q-Yb</b> compared to the one for <b>H<sub>2</sub>SQ-Yb</b>. The <b>H<sub>2</sub>SQ</b> triad efficiently sensitized the Yb<sup>III</sup> luminescence while the chemical oxidation of <b>H<sub>2</sub>SQ</b> into <b>Q</b> induced strong modification of the absorption properties and thus a quenching of the Yb<sup>III</sup> luminescence for <b>Q-Yb</b>. In other words, both magnetic modulation and luminescence quenching are reached by the oxidation of the protonated semiquinone into quinone.
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