Tetranuclear Ln(III) complexes with 2-sulfobenzoate and their three-dimensional supramolecular frameworks consolidated through hydrogen-bonding and intermolecular O···π interactions

Two isostructural tetranuclear Ln(III) complexes {[Ln2(2-SB)3(phen)3(H2O)2]·4.5H2O}2 (Ln = Er (1), Y (2)) with 2-sulfobenzoate (2-SB) as bridge and 1,10-phenanthroline (phen) as terminal are synthesized and characterized through single-crystal X-ray diffraction, IR and near-infrared luminescence spectroscopy. The tetranuclear structural motifs are further assembled into three-dimensional supramolecular architectures through hydrogen-bonding and O(sulfonate)⋯⋯π(phen) interactions. A hexamer (H2O)6 cluster with novel configuration is revealed in the conglomeration of the tetranuclear motifs.