A 3D Compound Based on Semi-rigid Tricarboxylato-Bridged Co(II): Synthesis, Crystal Structure and Magnetism

With the assistance of N-donor ligand 1,4-bi(1H-imidazol-1-yl)benzene (1,4-bib), Co(II) reacts with 5-((4-carboxyphenoxy)-methyl)isophthalic acid (H 3 L) under hydrothermal condition to form a compound [Co 3 (L 3− ) 2 (1,4-bib) 4 ]·4H 2 O ( 1 ). The both contributions of semi-rigid tricarboxylic ligand L 3− and rigid 1,4-bib leads to predictably high dimensional structure. Compound 1 crystallizes in a complicated 3D network, which can be simplified as 3,6,8- conn topology. For the correlation between structure and property, the structural feature is well reflected in the magnetic property: a carboxylato group bridges two Co(II) paramagnetic ions. Within the dinuclear subunit, significant anti-ferromagnetic interactions are observed. Graphical Abstract A novel 3D Co(II) compound 1 is formed via hydrothermal reaction in this work. Antiferromagnetic interactions between two neighbour cations coordinated by one carboxylato group are observed.