Two Series of Substituent‐Group‐Directed Adipate‐Based Lanthanide Coordination Polymers: Syntheses, Structures, Photoluminescence, and Magnetism

Abstract

Two series of lanthanide‐organic coordination polymers (CPs) [Ln2(L1)3(H2O)4] [Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), and Dy (6), H2L1 = 3‐methyl‐adipic acid] and [Ln4(L2)6(H2O)4] [Ln = Nd (7), Sm (8), Eu (9), Gd (10), Tb (11), and Dy (12), H2L2 = 3‐tert‐butyl‐adipic acid] have been synthesized by the solvothermal reactions of lanthanide salts with two types of flexible substituent adipates. All of these CPs were characterized by single‐crystal X‐ray diffraction, elemental analysis, IR spectroscopy, powder X‐ray diffraction, and thermal analysis. Structural analyses reveal that CPs 1–6 and 7–12 are isostructural, respectively. CPs 1–6 show a two‐dimensional (2D) layer constructed from the 3‐methyl‐adipate anions bridging two types of binuclear Ln2 units. The adjacent 2D layers are further extended into a three‐dimensional (3D) supramolecular framework through the hydrogen‐bonding interactions. CPs 7–12 also exhibit a 2D structure. The carboxyl groups of 3‐tert‐butyl‐adipate link four types of TbIII ions to form a one‐dimensional (1D) inorganic TbIII chain. The neighboring 1D inorganic TbIII chains are further connected by the 3‐tert‐butyl‐adipate anions to construct a 2D network. The effect of substituent groups on the formation of adipate‐based lanthanide CPs as well as the photoluminescence and magnetic properties of 1–12 were investigated in detail.