Visible and near-infrared emitting heterotrimetallic lanthanide–aluminum–sodium 12-metallacrown-4 compounds: discrete monomers and dimers. Issue 15 (30th March 2022)

• Record Type: Journal Article
• Authors: Eliseeva, Svetlana V.; Travis, Jordan R.; Nagy, Sarah G.; Smihosky, Alyssa M.; Foley, Collin M.; Kauffman, Abigail C.; Zaleski, Curtis M.; Petoud, Stéphane
• Is Part Of: Dalton transactions. Volume 51:Issue 15(2022)
• Page Start: 5989
• Page End: 5996
• Publication Date: 2022-03-30
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d1dt04277g
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The terbium-aluminum metallacrowns (MC), TbAl4 Na (left image & capillary) and Tb2 Al8 Na2 (right image & capillary) emit green light. Tb2 Al8 Na2 has a quantum yield value of 43.9%, the highest value observed in the solid state to date for a Tb III MC. Abstract : The luminescence properties of two types of heterotrimetallic aluminum–lanthanide–sodium 12-metallacrown-4 compounds are presented here, LnNa(ben)4 [12-MCAl(III)N(shi) -4] (LnAl4 Na ) and {LnNa[12-MCAl(III)N(shi) -4]}2 (iph)4 (Ln2 Al8 Na2 ), where Ln = Gd III, Tb III, Er III, and Yb III, MC is metallacrown, ben − is benzoate, shi 3− is salicylhydroximate, and iph 2− is isophthalate. The aluminum–lanthanide–sodium metallacrowns formed with benzoate are discrete monomers while, upon replacement of the benzoate with the dicarboxylate isophthalate, two individual metallacrowns can be joined to form a dimer. In the solid state, the terbium version of each structure type displays emission in the visible region, and the erbium and ytterbium complexes emit in the near-infrared. The luminescence lifetimes ( τ obs ) and quantum yields have been collected under ligand excitation ( Q LLn) for both LnAl4 Na monomers and Ln2 Al8 Na2 dimers. Several of these values tend to be shorter (luminescence lifetimes) and smaller (quantum yields) than the corresponding values recorded for the structurally similar gallium–lanthanide monomer and dimer 12-MC-4 molecules. However, the quantum yield value recorded for the visible emitting Tb2 Al8 Na2 dimer, 43.9%, is the highest value observed in the solid state to date for a Tb III based metallacrown.