879555-50-7Relevant academic research and scientific papers
Multiple regulated assembly, crystal structures and magnetic properties of porous coordination polymers with flexible ligands
Sun, Chang-Yan,Zheng, Xiang-Jun,Gao, Song,Li, Li-Cun,Jin, Lin-Pei
, p. 4150 - 4159 (2005)
Four novel coordination polymers of NiII and CoII with flexible ligands, namely [Ni(oba)(bpe)] n·nH2O (1), [Co(oba)-(bpe)]n (2), [Ni2(oba)2(bpy)2(H2O) 2]n·nbpy (3), and [Co(oba)-(bpy) 1/2]n (4) [H2oba = 4,4′-oxybis(benzoic acid), bpe = 1,2-bis(4-pyridyl)ethane, bpy = 4,4′-bipyridine] were synthesised by hydrothermal reactions and characterised by single-crystal X-ray diffraction, elemental analysis and IR spectroscopy. The NiII ions in complex 1 are linked by flexible oba and bpe ligands to form square-grid-like corrugated sheets. These sheets are interpenetrated with each other, resulting in the formation of a 3D porous network with lattice water molecules in the channels. The variable temperature X-ray diffraction analysis shows that the framework is stable up to 300°C despite the complete removal of the lattice water molecules during the heat treatment. Complex 2 can be regarded as possessing a α-polonium-related topology. Triple interpenetration occurs to form a nonporous structure. In complex 3, the oba and bpy ligands link NiII ions into 1D train-like boxes. These boxes are entangled, with the aid of hydrogen bonds, leading to the formation of a 3D porous supramolecular architecture. Free bpy ligands reside in the channels. The CoII ions in complex 4 are linked by oba and bpy ligands to form a complicated 3D coordination polymer. The lattice water molecules in complex 1 and free bpy ligands in complex 3 can be regarded as templates that play an important role in the formation of the porous structures of complexes 1 and 3. The magnetic properties of complexes 1, 2, and 4 have also been investigated. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
