Lanthanide coordination polymers of viologen carboxylic acid: Crystal structures and luminescence response tuning

Abstract

In the context, using solvo-thermal method, three isostructural lanthanide coordination polymers with viologen as linker ([m-H2bpybdc], m-bpybdc = 1,1′–bis(3-carboxyphenyl)-4,4′-bipyridinium), whose basic frameworks are formulated as [Ln(m-bpybdc)(H2O)3NO3] (Ln-CP, Ln = Sm, Eu and Gd). Among the crystal structures of Eu-CP and Gd-CP are determined, which belong to the one-dimensional ribbon structure. The physical characterization and especially the luminescence properties of them are studied in details. Furthermore, it is found that the coordinated water molecules can hinder the photo-induced electron transfer process (PET) of these viologen based lanthanide coordination polymers. So Eu-CP is selected to try to check water molecule in solvents for its photo response. These results show useful data for the structure, luminescence and photo response application of viologen based lanthanide coordination polymers.