Syntheses, Crystal Structures, and Magnetic Properties of Metal–Organic Hybrid Materials of Mn(II)/Co(II): Three-Fold Interpenetrated α‑Polonium-like Network in One of Them

Three new 1,4-phenylenediacrylate bridged Mn­(II) and Co­(II) complexes of molecular formulas {[Mn₂­(ppda)­(phen)₄­(H₂O)₂]­(ppda)₂­(H₂O)} (<b>1</b>), {[Co­(ppda)­(dpyo)­(H₂O)₃]·4­(H₂O)}<i>_n</i> (<b>2</b>), and {[Co­(ppda)­(bpe)]·(0.5H₂O)}_<i>n</i> (<b>3</b>) [ppda = 1,4-phenylenediacrylate; phen = 1,10-phenanthroline; dpyo = 4,4′-dipyridyl <i>N</i>,<i>N</i>′-dioxide; bpe = 1,2-bis­(4-pyridyl)­ethane] have been synthesized and characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction studies, and low-temperature magnetic measurements. The structural determination reveals that complex <b>1</b> is a discrete dinuclear species, <b>2</b> is a 1D polymeric chain, while <b>3</b> is a three-fold interpenetrated α-polonium network. Hydrogen-bonding interactions, formed by coordinated and/or lattice water molecules with ppda oxygen and π–π stacking interactions of aromatic rings, lead to a 3D supramolecular architecture in both complexes <b>1</b> and <b>2</b>. Low-temperature magnetic study shows antiferromagnetic coupling in all the complexes. In addition, their electronic and fluorescent spectral properties have been investigated