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A novel three-dimensional (3D) polymer [Cd(SC3H5N2)2]n (SC3H5N2 = deprotonated 1,3-imidazolidine-2-thione) (1) was synthesized. The deprotonated 1,3-imidazolidine-2-thione ligand has been found at cadmium for the first time. The single-crystal X-ray diffraction shows that the deprotonated 1,3-imidazolidine-2-thione ligand contributes greatly to the formation of the 3D framework and the helical structure. Compound 1 exhibits blue fluorescence at 494 nm in the solid state upon excitation at 372 nm.

Three novel homochiral helical metal−organic frameworks (MOFs), namely [Zn(LTP)2]n (1), [Cd(LTP)2]n (2), and [Ni(LTP)2]n (3) (LTP = l-thioproline), have been synthesized and characterized. X-ray crystallographic analysis shows that all the three complexes consist of homochiral left-handed or right-handed helical chains. Complex 1 exhibits 1-D Zn-carboxyl right-handed helical chains constructed by pentacoordinated Zn2+ ions. Complex 2 shows a 2-D homochiral coordination framework with (4, 4) topology based on Cd-carboxyl right-handed helical chains in which Cd2+ ions are 6-fold coordinated. There are various hydrogen bonds between the adjacent helical chains in 1 and 2 which connect them into 3-D supramolecular networks. Complex 3 also exhibits a 2-D homochiral layer structure with (4, 4) topology containing Ni-carboxyl left-handed helical chains. The luminescence properties of 1 and 2 have been investigated briefly.

Five novel silver (Ι) complexes with 1,3-imidazolidine-2-thione ligand formulated as [Ag2(η1-SC3H6N2)6]SO4 (1), [Ag2(μ2-SC3H6N2)2(η1-SC3H6N2)4](NO3)2 (2), [Ag(μ2-SC3H6N2)Br]n (3), [Ag2(μ2-SC3H6N2)3(CH3COO)2]n (4), [Ag(μ2-SC3H6N2)Cl]n (5) have been synthesized under similar conditions except for different anions and solvents. They are structurally characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. Complex 1 is a binuclear complex, with SO42− anions as the counteranions. Complex 2 is a molecular binuclear silver cluster, with NO3− anions as the counteranions. Complex 3 shows a novel 2D lamella structure constructed by the S atom of 1,3-imidazolidine-2-thione ligand and Br− anions, and exhibits 12-membered metallacyclic rings in its structure. Complex 4 is a novel 2D layered polymer with a graphite-like array of silver (I) ions, with CH3COO− anion coordinated to silver(I) ions by O atom. Complex 5 shows a 3D diamond-like network structure constructed by the sulfur atom of 1,3-imidazolidine-2-thione ligand and Cl− anions.

Five novel complexes, Co(OBt)2 · 7H2O (1) (OBt = 1-hydroxybenzotriazole ion), Ni3(OBt)6 · 6H2O (2), [Ag(OBt)(HOBt)]n (3), [Zn(OBt)2]n (4) and [Cu2(OBt)4 · 3H2O]n (5) were synthesized by hydrothermal method and characterized by elemental analysis, IR spectroscopy, TGA, XRPD, and single-crystal X-ray diffraction. The results from single-crystal X-ray diffraction indicate that 1–5 are zero-dimensional (0D), zero-dimensional, one-dimensional (1D), and three-dimensional (3D) frameworks, respectively. In particular, 3 is twin crystal; 4 possesses of double-stranded chains; 5 crystallizes in orthorhombic space group P212121 with a helical chain in its structure. The luminescence properties and the magnetic properties of the five complexes were investigated.

The eight-nickel-capped polyoxoazonickelate, [Ni(20)(OH)(24)(MMT)(12)(SO(4))](NO(3))(2).6H(2)O (1; MMT = 2-mercapto-5-methyl-1,3,4-thiadiazole), has been synthesized, which has an alpha-Keggin structure with eight nickel caps. In this structure, the polyatom is the late transition metal Ni(II); the central heteroatom is S, and the organic terminal ligand becomes the primary part of the Keggin structure. This is a Keplerate-type cluster, which shows a central Ni(II)(12) cuboctahedron formed by the 12 Ni(II) centers of the classical alpha-Keggin core and a Ni(II)(8) hexahedron formed by the eight nickel caps.

We report a catalytic eight-cobalt-capped α-Keggin polyoxoazocobaltite with a highly symmetric structure completely constructed from the late transition-metal Co(II) as a poly atom, [Co(20)(OH)(24)(MMT)(12)(SO(4))](NO(3))(2)·6H(2)O (1) (MMT: 2-mercapto-5-methyl-1,3,4-thiadiazole). To the best of our knowledge, this is the first homometallic Co(II) magnetic cluster bearing Keggin structure. It can serve as a potential catalyst in the styrene polymerization.