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A series of new mixed-metal Ru(II)-Ir(III) trinuclear complexes have been prepared and characterized, together with their mononuclear parents and a series of closely related dinuclear and trinuclear homometallic Ru(II) and Ir(III) species, and their absorption spectra and luminescence properties (both at 77 K in rigid matrix and at room temperature in fluid solution) have been studied. The absorption spectra and luminescence properties of the Ru(II) species and subunits are dominated by metal-to-ligand charge-transfer (MLCT) transitions and excited states, whereas ligand centered (LC) transitions and excited states govern the spectroscopic and photophysical properties of most of the Ir(III) species here studied, with MLCT states playing an important role when cyclometalated Ir(III) subunits are present. Each metal-based subunit retains in the multinuclear arrays its own spectroscopic properties, but in the case of the mixed Ru-Ir species an efficient, additional decay channel is opened for the excited states involving the Ir-centered subunits, that is, photoinduced energy transfer to the lower-lying MLCT state(s) involving the Ru centers.

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United for white: Bright white silica single layers are obtained by exploiting efficient red (Eu3+) and green (Tb3+) luminescent antenna complexes and a blue‐light‐emitting carbazole derivative (see picture). By combining the mild sol–gel solution route with the peculiar chemical and photophysical behaviour of selected light‐emitting species, white luminescent materials with colour stability and shaped architecture are easily obtained through a molecular design strategy.

Eu(III) and Tb(III) antenna complexes employing different units−phenanthroline and acetophenone derivatives−for light absorption and sensitization of the lanthanide (Ln) emitting states, have been synthesized and successively anchored in silica layers by the sol−gel technique. The luminescence properties of the complexes, preliminarily studied in H2O and D2O solutions, were improved in the oxide host matrix, showing the effectiveness of the employed synthesis route for the preparation of efficient molecular-based light-emitting materials. All the prepared films were highly transparent and homogeneous and displayed a bright red (Eu3+) or green (Tb3+) luminescence notwithstanding the low luminophore content (Ln/Si = 1/400 or 1/100 molar ratios) and limited film thickness (≤140 nm). It is worth highlighting that the silica layers containing the Tb3+ complex bearing an acetophenone derivative as an antenna are characterized by photoluminescence quantum yields as high as 45%.