Anionic Metal–Organic Frameworks of Bismuth Benzenedicarboxylates: Synthesis, Structure and Ligand‐Sensitized Photoluminescence

Four organic–inorganic bismuth benzenedicarboxylate (bdc)frameworks, [Bi(1,4‐bdc) 2 (dmf)] · (dma)(dmf) 2 ( 1 ), [Bi(1,4‐bdc) 2 ] · (dma)(dmf) ( 2 ), [Bi 4 (1,4‐bdc) 7 (HIm)] · (dma) 2 (dmf) 2 ( 3 ) and [Bi(1,4‐bdc) 2 ] · (dma) ( 4 ) (where dma = dimethyl ammonium cation, HIm = imidazole and dmf = dimethylformamide) have been synthesized under solvothermal conditions, and their structures were determined by single‐crystal X‐ray diffraction. Compound 1 has a layer structure, whereas compounds 2 – 4 have three‐dimensional structures. All four frameworks are anionic and contain dma cations within cavities in their structures. Compounds 1 – 3 also contain coordinated and/or guest dmf molecules. The topologies of compounds 1 – 3 have 4‐connecting nodes; the layer structure in 1 is a corrugated (4,4)‐connected square lattice, but the three‐dimensional structures of 2 and 3 adopt the (dia) net topology. Compound 4 has a 6‐connecting node with a (pcu) net topology. The BiO n polyhedra are hemidirected with a stereochemically active lone pair of electrons in 2 , but holodirected with astereochemically inactive lone pair of electrons in 1 , 3 and 4 . Tb 3+ ‐ and Eu 3+ ‐doped and co‐doped 3 and 4 emit intense, ligand‐sensitized green, red or orange luminescence, respectively.