Synthesis, structure and properties of terephthalate-bridged copper (II) polymeric complex with zigzag chain

The complex, {[Cu L(μ2-ta)](CH3OH)2}n (L=N,N-dimethyl-N′-(pyrid-2-ylmethyl)-ethylene-diamine, ta=terephthalic acid dianion), has been synthesized. X-ray analyses revealed that the copper atom exhibits a distorted square pyramidal geometry, with three nitrogen atoms from the tridentate ligand and two carboxylato-oxygen atoms from different tas. Each ta ligand adopts a μ2-bridging mode with a typical average Cu–O distance (1.945–2.204 Å), and the tridentate ligand acts as a terminal ligand with a typical Cu–N distance (1.992–2.087 Å). Thus, each ta ligand links two metal centers and each metal center connects two ta ligands to form the zigzag chain structure. Variable temperature magnetic measurement of the complex shows that a weak ferromagnetic interaction between the copper(II) ions.