A series of new isostructural Ti-oxo clusters containing bridging bidentate 1,n-alkane diolate ligands with the formula [Ti4O4(O2PR2)4{O(CH2)nO}2] (R = Ph, n = 2–5; R = Cy, n = 2–4) were prepared by a...

Titanium-oxo clusters can undergo photochemical reactions under UV light, resulting in the reduction of the titanium-oxo core and oxidation of surface ligands. This is an important step in photocatalytic processes in light-absorbing Ti/O-based clusters, metal–organic frameworks, and (nano)material surfaces; however, studying the direct outcome of this photochemical process is challenging due to the fragility of the immediate photoproducts. In this report, titanium-oxo clusters [TiO(OiPr)(L)]n (n = 4, L = O2PPh2, or n = 6, L = O2CCH2tBu) undergo a two-electron photoredox reaction in the single-crystal state via an irreversible single-crystal to single-crystal (SC-SC) transformation initiated by a UV laser. The process is monitored by single crystal X-ray diffraction revealing the photoreduction of the cluster with coproduction of an (oxidized) acetone ligand, which is retained in the structure as a ligand to Ti(3+). The results demonstrate that photochemistry of inorganic molecules can be studied in the single crystal phase, allowing characterization of photoproducts which are unstable in the solution phase.

Luminescent emitters based on lanthanide ions are of ubiquitous importance in the biological sciences, but typically need sensitisation from a covalently attached adjacent chromophore – an “antenna” ....