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Changing N-substituents to modify energy gaps is important for the diverse applications (photochromism, photocatalysis, etc.) of viologen-based compounds. In situ N-substitution using alcohols under solvothermal and acidic conditions is an effective and common synthetic method for viologen-templated metal halides. In this work, we found that replacing alcohols with alkenes could reduce the reaction temperature dramatically to room temperature. A new cis/trans-viologen-templated bromoplumbate with a novel 1-D chain structure built by edge-sharing planar [Pb3Br9]3− oligomers was successfully obtained. This bromoplumbate hybrid has a narrower energy gap compared with bulk PbBr2, which has been well explained by linear optical response spectra calculations and PDOS analysis.

Two bifunctional 1H-tetrazolate-5-carboxylate ligands with different flexibilities, H2tza (1H-tetrazolate-5-acetic acid) and H2tzf (1H-tetrazolate-5-formic acid), were employed in the construction of zinc(II) complexes in the presence/absence of secondary ligands such as 2,2′-bipy and 4,4′-bipy. Three tza coordination polymers and two tzf dinuclear complexes, namely [Zn(tza)(H2O)]n (1), [Zn3(tza)2Cl2(2,2′-bipy)2(H2O)2]n (2), [Zn2(tza)2(4,4′-bipy)]n (3), [Zn(tzf)(H2O)3]2·2H2O (4) and [Zn(tzf)(2,2′-bipy)(H2O)]2·H2O (5), were hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Polymer 1 is a 3-D two-fold interpenetrating diamond-like network with tetranuclear [Zn(COO)]4 clusters as tertiary building units (TBUs) and µ3-κN3:κO2:κO1,N1 bridging tza as linkers. Polymer 2 presents a 2-D structure formed by the linkage of 1-D Zn-carboxylate [Zn(COO)]n helical chains and µ3-κN4:κO2:κO1,N1 bridging tza. In 3, 2-D (4,4) nets are built up with dinuclear [Zn(COO)]2 clusters and µ3-κN4:κO2:κO1,N1 bridging tza, which are pillared through 4,4′-bipy to gain a 3-D self-penetrating LB-1 (446108) topology. In dinuclear complexes 4 and 5, two Zn(II) atoms are bridged by a tzf ligand in a µ2-κN2:κO1,N1 fashion. The results denote that tetrazolate-5-carboxylate ligands can adopt variable coordination modes in the formation of the complexes, and different Zn-carboxylate aggregates can serve as tertiary building units (TBUs). The effects of the nature of tetrazolate-5-carboxylate ligands and secondary ligands, and hydrothermal reaction conditions on the structural topologies of the obtained complexes have been investigated. The photoluminescent properties and thermal stabilities of 1–5 have also been discussed.

A novel inorganic–organic hybrid [Cu(2,2′-bipy)2I]2n(PbI3)2n·nDMF·nH2O (1), which exhibits diplex single-crystal-to-single-crystal transformation, can transform to a guest molecule released compound [Cu(2,2′-bipy)2I]n(PbI3)n (1a) by thermal induction, or to both a guest molecule released and ligand exchanged compound [Cu(2,2′-bipy)3]n(Pb2I6)n (1b) by solvent induction.

A series of one-dimensional (1-D) N-succinopyridine-based complexes: [Cu(L−)(H2O)2]Cl·2H2O (1), [Pr(L−)(H2O)4]Cl2 (2), [Ln(L−)(H2O)5]Cl2·3H2O (Ln = Eu (3), Gd (4)), and [Er(L−)(H2O)4]Cl2·H2O (5) (HL = N-succinopyridine (−OOC–CH(N+C5H5)–CH2–COOH)) have been prepared and characterized by single-crystal X-ray diffraction. The frameworks of complexes 1, 2 and 5 constructed from dinuclear metal building blocks exhibit 1-D double-strand loop-like chains; these chains are further connected to each other by hydrogen bonds forming a 3-D supramolecular architecture. Whereas complexes 3 and 4 feature hydrogen bonding 2-D supramolecular networks assembled from 1-D chains that are constructed from mononuclear metal building blocks. The effects of different metal ions, steric hindrance and coordination diversities of HL on the polymeric architectures have been discussed. In addition, thermogravimetric and magnetic properties of these complexes were also investigated in this paper.

We investigate the impact of different derivatives of 1,4-diazabicyclo[2.2.2]octane on the crystal structures of iodoplumbates by systematically increasing the size of the same organic amine, and present two new 1-D iodoplumbates. Optical studies reveal the semiconductor characteristics of all as-synthesized iodoplumbate hybrids.

Two fluorescent cadmium complexes, [HL][CdCl2(H2O)2] (1) and [HL][CdBr2(H2O)2] (2) (HL = N-succinopyridine), have been prepared and characterized by single-crystal X-ray diffraction. Complex 1 contains a unique μ2-Cl bridged neutral 2D inorganic layer, which is further connected to isolated HL molecules by hydrogen bonds forming a hamburger-like OIO 2D supramolecular architecture. Complex 2 features a 3D supramolecular network assembly from 1D inorganic chains and discrete organic molecules through hydrogen bonds. Thermogravimetric, luminescent properties and theoretical calculations of 1 and 2 are also discussed. Moreover, UV-to-Vis tunable emissions for N-succinopyridine and 1 as well as blue-to-green tunable emission for 2 are observed.

The stabilization of the (SnS4)4− anion in the coordination of [Mn(phen)]2+ complexes brings about a novel compound {[Mn(phen)]2(SnS4)}n·nH2O (1), in which an unprecedented link mode of the (SnS4)4− anion is observed. Theoretical calculations indicate that TM complexes with big π-conjugated ligands, such as [Mn(phen)]2+, can serve as an excellent electron reservoir to stabilize the (SnS4)4− anion in 1, despite its strong condensation tendency. Magnetic measurements show the presence of strong antiferromagnetic interactions between the Mn2+ ions in 1.

NSF of China [20701037, 20801026]; NSF for Distinguished Young Scientist of China [20425104]; 973 program [2009CB939801]; Key Project from the CAS [KJCX2.YW.M10]; NSF of Fujian Province [2008I0026]

Using cyanide anions and sulfur simple substance as precursors of thiocyanate groups, three desired luminescent halogeno-thiocyano-d10 metal complexes, namely, [Me4N][Cu(SCN)Br] (1) with a 1-D to 2-D architecture constructed through C–H⋯Br hydrogen bonds, [Me4N][Cu(SCN)I] (2) with a 1-D to 3-D framework constructed through C–H⋯I hydrogen bonds, and [Me4N][Ag2(SCN)2Cl] (3) with a special 3-D nanoporous structure constructed by µ-chloride atoms connecting the 2-D neutral ∞2[Ag2(SCN)2] layers, have been solvothermally synthesized and all exhibit efficient luminescence. The luminescent behavior of the three complexes was illustrated through the density functional theory.