Hydrothermal Syntheses, Structures, and Properties of Three 3‐D Lanthanide Coordination Polymers that Form 1‐D Channels

We report the hydrothermal synthesis and crystal structure of isostructural lanthanide coordination polymers [Ln2(NDC)3(phen)2]·H2NDC [Ln = Tb (1), Ho (2) and Yb (3)] that feature 2,6‐naphthalenedicarboxylate (NDC) and 1,10‐phenanthroline (phen) ligands. The NDC ligands bridge the lanthanide ions in two different modes to form a 3‐D porous framework that accommodates large, neutral 2,6‐naphthalenedicarboxylic acid molecules as guests in the channels, stabilized through O−H···O hydrogen bonds to the NDC ligand. The effective dimension of the channel is ca. 6.0 × 8.2 Å. Thermogravimetric analysis shows that complex 2 remains stable up to 330 °C, which we confirmed also by powder X‐ray diffraction analyses. The framework collapsed upon the loss of the coordinating phen molecules. The Tb complex shows strong evidence of ferromagnetic coupling interactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)