Multifunctional Homochiral Lanthanide Camphorates with Mixed Achiral Terephthalate Ligands

Seven homochiral lanthanide camphorates with mixed achiral terephthalate ligands, namely, {Ln<sub>2</sub>(cam)<sub>2</sub>(bdc)(H<sub>2</sub>O)<sub>2</sub>}·DMF [Ln = Sm (<b>1</b>), Eu (<b>2</b>), Gd (<b>3</b>), Tb (<b>4</b>), Dy (<b>5</b>), Ho (<b>6</b>), Er (<b>7</b>); d-H<sub>2</sub>cam = d-(+)-camphoric acid; H<sub>2</sub>bdc = 1,4-benzenedicarboxylic acid; DMF = <i>N</i>,<i>N</i>′-dimethylformamide], have been solvothermally synthesized. Single-crystal X-ray diffraction analyses reveal that compounds <b>1</b>−<b>7</b> are isostructural and crystallize in orthorhombic, chiral space group <i>P</i>2<sub>1</sub>2<sub>1</sub>2<sub>1</sub>. These structures feature three-dimensional open frameworks based on rodlike [Ln<sub>2</sub>(OCO)<sub>6</sub>(H<sub>2</sub>O)<sub>2</sub>]<sub><i>n</i></sub> secondary building units, with the guest DMF molecules occupying the void space of the host {Ln<sub>2</sub>(cam)<sub>3</sub>(bdc)(H<sub>2</sub>O)<sub>2</sub>} framework. The photophysical and magnetic properties of some of these complexes have been investigated. Notably, the terbium compound <b>4</b> is highly emissive with a quantum yield of 63.68%. Additionally, thermogravimetric analyses, variable-temperature IR spectrscopy, and powder X-ray diffraction of <b>2</b> as a representative were performed to determine its thermal stability, which indicates that the framework still remains intact until 300 °C.