New Coordination Polymers of Lanthanide(III) with Tetrazole-1-acetic Acid: Synthesis, Crystal Structures, and Magnetic Properties

Abstract

New coordination polymers {[Ln(tza)3(H2O)2]·mH2O}n (Ln = LaIII 1 and PrIII 2, m = 2; Ln = NdIII 3, m = 1.5) and {[Sm2(tza)6(H2O)5]·H2O}n 4 (Htza = tetrazole-1-acetic acid) have been synthesized and characterized by IR spectroscopy, elemental analysis, X-ray crystallography, and magnetic measurements. The Htza ligand coordinates to the lanthanide cations through the carboxylate group in a monodentate, bridging bidentate coordination mode or bridging tridentate to two metal centres. Complexes 1 and 2 are isostructural. Complex 3 has a similar structure to 1 and 2, but the arrangement of ligands has changed. Complex 4 consists of two types of metallic molecules. Magnetic measurements show weak antiferromagnetic coupling between the metal centres in complexes 2 and 3.