Hydrothermal Preparation, Crystal Structure, Photoluminescence and UV-Visible Diffuse Reflectance Spectroscopic Properties of a Novel Mononuclear Zinc Complex.

A novel mononuclear zinc complex [ZnL(Phen)(H2O)]·H2O containing the mixed ligands of Phen (Phen = 1,10-phenanthroline) and 3-hydroxy-2-methylquinoline-4-carboxylic acid (HL) was prepared by hydrothermal synthesis and its crystal structure was characterized by X-ray single-crystal diffraction method. The title complex crystallizes in the orthorhombic systems and forms monomeric units. The molecules in the title complex are connected through the interactions of hydrogen-bonding and ????? interactions to give a three-dimensional (3D) supramolecular structure. The fluorescence result discovers a wide emission band in the violet blue region. Time-dependent density functional theory (TDDFT) calculations reveal that this emission can be attributed to ligand-to-ligand charge transfer (LLCT). Solid-state diffuse reflectance shows there is a wide optical band gap.

Preparation, Structure, Photoluminescent and Semiconductive Properties, and Theoretical Calculation of a Mononuclear Nickel Complex with 3-Hydroxy-2- Methylquinoline-4-Carboxylato Ligand.

A novel nickel complex with mixed ligands [Ni(L)2(EtOH)2(MeOH)2] (HL = 3-hydroxy-2-methylquinoline-4-carboxylic acid) has been synthesized through solvothermal reaction and its crystal structure was determined by single-crystal X-ray diffraction technique. Single-crystal X-ray diffraction analyses reveals that the title compound crystallizes in the triclinic system of the P-1 space group, and exists as isolated mononuclear complex. The intermolecular hydrogen bonds lead to the formation of chains, and the layered supramolecular structure is formed by the strong ααααα stacking interactions. Solid-state photoluminescent characterization reveals that the title compound has an emission in the green region. Time-dependent density functional theory (TDDFT) calculation shows that the nature of the photoluminescence of the title compound originates from the ligand-to-ligand charge transfer (LLCT; from the HOMO of the p-orbital of ligand HMCA to the LUMO of the oxygen atoms). A wide optical band gap of 2.25 eV is found by the solid-state UV/vis diffuse reflectance spectrum.

Erratum: (Dimethyl sulfoxide-κO)[3-hydr-oxy-2-hydroxy-methyl-2-(3-meth-oxy-2-oxido-benzyl-ideneamino-κO,N)propanolato-κO]dioxomolybdenum(VI). Corrigendum.

The crystal structure of the title compound in the paper by Sui, Fang, Luo, Chen & Zhou [Acta Cryst. (2006), E62, m1994-m1996] has been rerefined to allow for identification of a disordered dimethyl sulfoxide ligand.[This corrects the article DOI: 10.1107/S1600536806028832.].

catena-Poly[bis{mu-dihydrogen [(5-carboxypentylimino)dimethylene]diphosphonato-kappa2O:O'}cadmium(II)].

The title compound, [Cd(C(8)H(18)NO(8)P(2))(2)](n), synthesized by hydrothermal methods, exhibits a layered structure in which the Cd(II) ion, occupying a centre of symmetry, is coordinated by six O atoms from four phosphonate ligands. The crosslinkage of CdO(6) octahedra by bridging phosphonate ligands results in a cadmium(II) phosphonate layer. Within the layer, there exists a 16-membered ring incorporating four -Cd-O-P-O- linkages. The uncoordinated carboxyl group of the ligand is oriented so that it penetrates the adjacent layer, taking part in hydrogen bonding to two uncoordinated phosphonate O atoms to form a CO(2)H/HO(2)P motif.

1-(2-Fluoro-benz-yl)-1-(2-fluoro-benz-yl-oxy)urea.

In the title hydroxy-urea derivative, C(15)H(14)F(2)N(2)O(2), the dihedral angle between the two benzene rings is 48.64 (19)°. The urea group forms dihedral angles of 48.1 (2) and 79.2 (2)° with the two benzene rings. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds occur, and further N-H⋯O links lead to chains of molecules.

Poly[mu2-4,4'-bipyridine-di-mu2-bromido-cadmium(II)], with novel colour-tunable fluorescence.

The title inorganic-organic hybrid complex, [CdBr2(C(10)H(8)N(2))]n, features two-dimensional [CdBr2(4,4'-bipy)]n (4,4'-bipy is 4,4'-bipyridine) neutral networks, based on the octahedral Cd atom coordinated by four mu2-Br and two mu2-4,4'-bipy at trans positions, yielding a CdBr(4)N(2) octahedron. It crystallizes in the orthorhombic system (Cmmm). All the crystallographically independent atoms are on special positions, namely Cd on mmm, Br on mm, N on mm2, and C on sites of symmetry m or mm2. Optical absorption spectroscopy reveals the presence of an optical gap of 3.76 eV, indicating that the complex is a wide-gap semiconductor. Photoluminescence investigation reveals that the complex displays strong colour-tunable emissions, which might originate from a ligand-to-ligand charge-transfer (LLCT) transition. Thermogravimetric differential thermal analysis shows that the complex is thermally stable up to 493 K.

4,4'-Bipyridinium tetrabromocadmate(II) with strong fluorescence.

The title compound, (C10H10N2)[CdBr4], was synthesized via a hydrothermal reaction. Its structure features discrete 4,4'-bipyridinium cations and tetrahedral [CdBr4]2- anions linked into ion pairs by single N-H...Br hydrogen bonds. Photoluminescent investigation reveals that the title compound displays a strong emission in the blue region, which may originate from pi --> pi* charge-transfer interactions of the 4,4'-bipyridinium cations.

Bis(micro-di-2-pyridylaminato 1-oxide)bis[(trifluoroacetato)copper(II)] acetonitrile disolvate.

The crystal structure of the title compound, [Cu(2)(C(2)F(3)O(2))(2)(C(10)H(8)N(3)O)(2)].2CH(3)CN, contains discrete [Cu(2)(CF(3)COO)(2)(O-dpa)(2)] molecules (O-dpaH is di-2-pyridylamine 1-oxide) which have imposed crystallographic twofold symmetry and an acetonitrile molecule of solvation. The O-dpa(-) ligand is both bidentate and bridging, linking two Cu atoms with a separation of 3.4270 (11) A. Each Cu atom is surrounded by four coordinated atoms that are almost coplanar, with dimensions Cu-N = 1.940 (2) and 1.984 (3) A, and Cu-O = 1.912 (2) and 1.945 (2) A.