Three Mn(ii) metal–organic frameworks with the same chemical composition, but different topological structures and properties

Abstract

Solvothermal reactions of a novel multidentate ligand, 2,5-bis-(1,2,4-triazol-1-yl)-terephthalic acid (H₂TTPA), with MnCl₂ afforded three structurally distinct coordination polymers with the same formula, [Mn(TTPA)·H₂O]_n (Mn-(1–3)). Single-crystal X-ray diffraction analyses show that complex Mn-1 exhibits a binodal 3D framework with Schläfli symbol {4²·6·8³}, while Mn-2 displays a trinodal 3D framework with point symbol {4¹⁶·6¹²}{4⁴·6²}₂. Mn-3 shows a novel complicated topology, which is characterized as a 4,5,6-c net 3D framework. Further magnetic analysis discloses the antiferromagnetic (AF) behavior between Mn(II) ions in complexes Mn-2 and Mn-3.