Impact of\nSynthetic Variables on the Structural Diversity\nof Tb<sup>III</sup>-Carboxylate Frameworks: Gas Adsorption, Magnetism,\nand Organocatalysis Investigations

In this work, three unique Tb<sup>III</sup>-carboxylate\nframeworks\nwith the formula {[Tb<sub>2</sub>(OH)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>(abtc)]·2H<sub>2</sub>O}<sub><i>n</i></sub> (<b>1</b>), {[Tb<sub>2</sub>(abtc)<sub>1.5</sub>(H<sub>2</sub>O)<sub>3</sub>(DMA)]·H<sub>2</sub>O}<sub><i>n</i></sub> (<b>2</b>) and {[Tb<sub>3</sub>(abtc)<sub>2.5</sub>(H<sub>2</sub>O)<sub>4</sub>]·H<sub>3</sub>O}<sub><i>n</i></sub> (<b>3</b>), each displaying structural variations, have\nbeen successfully synthesized by the solvothermal reactions of Tb(NO<sub>3</sub>)<sub>3</sub>·6H<sub>2</sub>O with the azo-containing\nligand 3,3′,5,5′-azobenzene tetracarboxylic acid (H<sub>4</sub>abtc) under varying conditions. Detailed single-crystal X-ray\ndiffraction (SC-XRD) analysis manifested a remarkable diversity in\nthese structures, demonstrating various coordination patterns of Tb<sup>III</sup>-metal nodes with the carboxylate groups of the organic\nlinker, which contributed to the generation of intricate three-dimensional\n(3D) coordination networks with remarkable chemical resistance. Furthermore,\nframeworks <b>2</b> and <b>3</b>, characterized by porous\nnetworks containing two and three independent Tb<sup>III</sup>-metal\nnodes, respectively, were both demonstrated to be efficient heterogeneous\ncatalysts toward the cyanosilylation of imines under mild conditions\nwith excellent reusability. In addition, direct current (<i>Dc</i>) magnetic susceptibility measurements conducted on frameworks <b>1</b>, <b>2</b>, and <b>3</b> indicated that there\nwere obvious antiferromagnetic interactions among the Tb<sup>III</sup>-metal nodes, which suggests the involvement of intricate <i>intra</i>- and <i>intertrimer</i> exchange channels,\nadding another fascinating dimension to their physical properties.