Summary: | A new Ag/Cu bimetallic cluster [Ag<sub>10</sub>Cu<sub>6</sub>(bdppthi)<sub>2</sub>(C≡CPh)<sub>12</sub>(EtOH)<sub>2</sub>](ClO<sub>4</sub>)<sub>4</sub> (<b>1</b>, bdppthi = <i>N</i>,<i>N′</i>-bis(diphenylphosphanylmethyl)-tetrahydroimidazole) exhibited strong phosphorescent (PL) emission at 644 nm upon excitation at 400 nm. Removal of the coordinated EtOH molecules in <b>1</b> resulted in derivative <b>1a</b>, which exhibited significant red-shifted emission at 678 nm. The structure and PL of <b>1</b> was restored on exposure to EtOH vapor. Cluster <b>1a</b> also exhibited a vapor-chromic PL response towards other common organic solvent vapors including acetone, MeOH and MeCN. A PMMA film of <b>1a</b> was developed as a reusable visible sensor for MeCN.
|