Four one-dimensional lanthanide-phenylacetate polymers exhibiting luminescence and magnetic cooling/spin-glass behavior.

Four isostructural lanthanide coordination polymers with a phenylacetate (PAA) ligand, [Ln(PAA)(HO)] (Ln = Eu (1); Gd (2); Tb (3); Dy (4)), were synthesized under hydrothermal conditions. Complexes 1-4 display a one-dimensional (1D) wave chain structure bridged by the carboxylate of the PAA ligand, which was generated via the in situ decarboxylation of phenylmalonic acid. Magnetic studies suggest the presence of ferromagnetic LnLn coupling in the 1D chain of 1-4. Meanwhile, 2 has a significant cryogenic magnetocaloric effect with the maximum -ΔS of 26.73 at 3 K and 7 T, and 3 and 4 show interesting spin-glass behavior, which is rarely reported for Ln-containing complexes. Additionally, the solid-state photophysical properties of 1 and 3 display strong characteristic Eu and Tb photoluminescence emission in the visible region, indicating that Eu- and Tb-based luminescence are sensitized by the effective energy transfer from the ligand to the metal centers.