Visible and near-infrared luminescence of polycatenated cationic pyridinone lanthanide networks

A series of isomorphic lanthanide coordination polymers [Ln（Ⅲ）（MBP）2（NO3）2（Br）- 2C3H60] [Ln=Eu, Tb, Er, Yb, and Gd; MBP=N,N＇-methylene-bis（pyridin-4-0ne）] featuring polycatenated sql cationic network and incorporated bromide counter ion were prepared. Their visible and near-infrared （NIR） luminescence properties were characterized by steady-state excitation and emission spectra, as well as luminescence lifetimes and quantum yields. The D2d dodecahedron coordination geometry causes visible light excitations and strongly monochromatic emissions. The external heavy-atom environment induces remarkable en- hancement on the NIR emissions. The sensitization processes are revealed by analyzing the electronic properties of MBP ligand.

A series of isomorphic lanthanide coordination polymers [Ln(III)(MBP)_2(NO_3)_2(Br)?2C_3H_6O] [Ln=Eu, Tb, Er, Yb, and Gd; MBP=N,N′-methylene-bis(pyridin-4-one)] featuring polycatenated sql cationic network and incorporated bromide counter ion were prepared. Their visible and near-infrared(NIR) luminescence properties were characterized by steady-state excitation and emission spectra, as well as luminescence lifetimes and quantum yields. The D_(2d) dodecahedron coordination geometry causes visible light excitations and strongly monochromatic emissions. The external heavy-atom environment induces remarkable enhancement on the NIR emissions. The sensitization processes are revealed by analyzing the electronic properties of MBP ligand.