| A series of complexes, namely, [Cu(bpy)2(bpdc)2]·3H2O 1, [Zn(bpy)2(bpdc)2(H2O)2] 2,[Cd(bpy)2(bpdc)2(H2O)2] 3, [Ni(μ-(3,5-pmb)2(H2O)2] 4, [Cd3(3,5-pmb)2(bpdc)2] 5, [Ni(3,4-pmb)(bdc)0.5] 6, [Co(3,5-pmb)(bdc)0.5] 7, and [Cd(3,5-pmb)(bdc)0.5] 8, where bpy = 2,2'-bipyridine, bpdc =1,1'-biphenyl-2,2'-dicarboxylate, 3,5-pmb =3,5-bis[4-pyridylmethyleneoxyl]benzoate, 3,4-pmb = 3,4-bis[4-pyridylmethyleneoxyl]benzoate, bdc =1,4- benzenedicarboxylate, have been synthesized by hydrothermal method and structurallycharacterized. X-ray structural analysis reveals that 1, 2 and 3 are binuclear molecules. Ineach the two bpdc groups align the two opposing planer [M(pby)]2+ cations. The moleculesare connected by C-H…O hydrogen bonds,π…πstacking and C-H…πinteractions to formthree dimensional supramolecular networks. Complex 4 crystallizes in triclinic p-1 spacegroup in which two pmb ligands connect between two Ni atoms to form four memberedplanar circuit, next and previous circuits adopt almost perpendicular direction up- ordownward with respect to that in the middle, forming 1D zigzag polymeric chain spanningalong the a-axis, further converted via hydrogen bond to 3D supramolecular framework withrectangular void of dimesions 12.06×17.85 A parallel to the ab-plane. 5 is a 2D frameworkcrystallizes in monoclinic C2/c space group constructed by infinite number of wave-likemetal-oxygen 1D chains made by Cd3N4O12 clusters bridged via the carboxylate groups ofbpdc ligands, these chains are linked together by pmb ligands to form connected helices.Complex 6 is a three dimensional (3D) 3-fold interpenetrated diamondiod architecture andcrystallizes in monoclinic C2/c space group, in which each Ni(Ⅱ) atom is connected to fourother Ni(Ⅱ) centers, resulting in the formation of a diamondoid network, the long spacersbetween coordination sites result in large cavities with adamantanoid cages these cavities areeffectively filled by mutual interpenetration of other two independent equivalent frameworksto stabilize the network. Complex 7 is a (3D) 4-fold interpenetrated polyrotaxane andcrystallizes in monoclinic P2(1)/c space group, it constructed by four equivalent independent3D fragments each consists of ring and rod chains, and entangled by other equivalentindependent individual fragment in a way that the rod of one chain passes through the ring ofthe other, more over the two pairs of equivelent networks with rotaxane entanglement are theninterwoven by each other to give a 3D fourfold structure. Complex 8 is a 2D network inwhich two Cd(Ⅱ) center are bridged equivalently by four carboxylate groups of different pmband bdc ligand, forming a paddle wheel secondary building unit (SBU) (CdO4N), the fivecoordination atoms in (CdO4N) occupy the vertex of square pyramidal structure. Complexes 3,5 and 8 exhibit strong luminescent properties in solid state at room temperature. The thermalstability for 4, 5 have also been studied.
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