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Copper-based nanomaterials have attracted tremendous interest due to their unique properties in the fields of photoluminescence and catalysis. As a result, studies on the correlation between their molecular structure and their properties are of great importance. Copper nanoclusters are a new class of nanomaterials that can provide an atomic-level view of the crystal structure of copper nanoparticles. Herein, a high-nuclearity copper nanocluster with 81 copper atoms, formulated as [Cu81(PhS)46(tBuNH2)10(H)32]3+ (Cu81), was successfully synthesized and fully studied by X-ray crystallography, X-ray photoelectron spectroscopy, hydrogen evolution experiments, electrospray ionization mass spectrometry, nuclear magnetic resonance spectroscopy, and density functional theory calculations. Cu81 exhibits extraordinary structural characteristics, including (i) three types of novel epitaxial surface-protecting motifs; (ii) an unusual planar Cu17 core; (iii) a hemispherical shell, comprised of a curved surface layer and a planar surface layer; and (iv) two distinct, self-organized arrangements of protective ligands on the curved and planar surfaces. The present study sheds light on structurally unexplored copper nanomaterials and paves the way for the synthesis of high-nuclearity copper nanoclusters.

A series of ten new lanthanide complexes, [Ln2(PA)6(bipy)2]·4H2O·2bipy (Ln = Eu 1, Tb 2, Ce 3, Gd 4, Nd 5, Pr 6, Sm 7, Yb 8) and [Ln2(PA)6(bipy)2]·4H2O (Ln = Ce 9 and Er 10) (HPA = 3-(4-hydroxyphenyl)propanoic acid and bipy = 2,2′-bipyridine), have been synthesized and characterized by microanalysis, FTIR and single crystal X-ray diffraction. The complexes 1–8 and 10 are isostructural and contain two crystallographically equivalent Ln3+ ions having a coordination number 9 with distorted monocapped square-antiprism geometries in which the PA ligands adopt bridging, bidentate chelating, and tridentate chelating bridging modes to coordinate with the Ln3+ ions, while complex 9 possesses a tricapped trigonal prism geometry where only bridging, bidentate chelating modes are adopted by the PA ligands. All the complexes display a 2D supramolecular layered framework held by weak C–H⋯π, π⋯π and O–H⋯O intermolecular interactions. These interactions have been validated by Hirshfeld surface analysis. Additionally, emission studies indicated that amongst all the complexes, 1 and 2 can act as luminescent sensors for the detection of nitrobenzene and Cu2+ ions. The limits of detection (LODs) using both 1 and 2 for nitrobenzene are 3.66 and 3.71 ppm, respectively and for Cu2+ ions, they are 2.11 and 2.99 ppm, respectively.

Three new silver–chalcogenide clusters protected by naphthyl ligands are described in this work, namely [Ag14(SCH2C10H7)6(CF3COO)8(DMAc)6] (1), [Ag30(SCH2C10H7)18(CrO4)2(DMAc)2 (CF3COO)8] (DMAc = dimethylacetamide) (2) and {Ag12(SCH2C10H7)6(CF3COO)4(CH3CN)6(Cr2O7)}n (3). Their crystal structures were studied by X-ray crystallography, and they show hollow-core–shell (1), template-core–shell (2) and 1D infinite (3) structures, respectively. The luminescence properties of cluster 1 were investigated, which showed interesting thermochromic variation from red to bright yellow. Moreover, the chromate ions were proven to act as templates in forming the silver clusters through a series of experiments to prepare compounds 2 and 3, which could be considered as derivatives of cluster 1.

ZnO:YAG-based metal-insulator-semiconductor (MIS) diodes with various insulators were synthesized on an indium tin oxide (ITO) glass by ultrasonic spray pyrolysis. SiO2and MnZnO (MZO) were separately used as insulators. X-ray diffraction revealed the crystalline structure of the ZnO:YAG film. The photoluminescence (PL) properties of the ZnO:YAG film were studied and the color of photoluminescence was found to be almost white. The electrical properties of the diodes with different insulators and thicknesses were compared. The diode with the SiO2insulator had a lower threshold voltage, smaller leakage current, and a higher series resistance than that with the MZO insulator layer.

Three new coordination polymers, namely, [ML(H2O)]n (M = Co (1), Zn (2)) and [CuL(DMF)]n (3), have been hydrothermally synthesized through the reaction of bifunctional ligand 5-((2-methyl-1H-imidazol-1-yl)methyl)benzene-1,3-dioic acid (H2L) with divalent cobalt, zinc and copper salts, and structurally characterized by elemental analysis, IR and X-ray diffraction. Both complexes 1 and 2 are two-fold interpenetration 3D frameworks. Complex 3 exhibits (3,6)-connected framework with (4.62)2(42.610.83) topology. Furthermore, UV–vis absorption spectra and powder X-ray diffraction (PXRD) were investigated as well.

Two isostructural metal–organic polymers, namely {[M(bce)(bib)]·solv}n (M = Co(II) and solv = CH3OH·H2O for 1; M = Ni(II) and solv = 0.5CH3OH·0·25H2O for 2) (H2bce = 1,2-bis(4-carboxy-phenoxy)ethane and bib = 2,3-bis(4-pyridyl)butane), have been synthesized and characterized. The structures of the two compounds show 2D → 2D parallel interpenetrated frameworks with polyrotaxane and polycatenane character. The magnetic behaviors of 1 and 2 indicate antiferromagnetic interactions within paddle-wheel units. Furthermore, the compound 1 exhibits relative high N2 uptake adsorption capacity.

A series of new pyridinyliminophosphorane bidentate ligands with different steric environments [(2-C6H4N)PPh2=NAr (NPN)] and their methylpalladium complexes [PdClMe(NPN)] were prepared. From the crystal structure analysis it is evident that the alkyl ligands are always trans to the pyridinyl nitrogen donor, revealing a σ-donating ability of the iminophosphorane. However, the two Pd−Cl bonds in [PdCl2(NPN)] are essentially the same length. Cationic palladium complexes catalyzed the copolymerization of norbornene/ethylene as well as CO/norbornene. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

A novel discrete open high-nuclearity nest-like silver thiolate cluster complex, [Ag33 S3 (StBu)16 (CF3 COO)9 (NO3 )(CH3 CN)2 ](NO3 ) (1), has been isolated with nitrate and S(2-) anions acting as structure-directing templates. Its similar nest-like structure has been assembled into an extended layer [Ag31 S3 (StBu)16 (NO3 )9 ]n (2) by adjustment of auxiliary ligand. More interestingly, both complexes exhibit temperature-dependent luminescence of high sensitivity with a large fluorescence enhancement (12-fold for 1, 21-fold for 2), which can be easily recognized by the naked-eye (dramatic red-shift Δ=104 nm for 1, larger Δ=113 nm for 2 at 77 K compared to those at 298 K). The correlation between luminescent thermochromism and temperature-dependent variation of the coordination modes of template NO3 (-) anion, Ag⋅⋅⋅S and Ag⋅⋅⋅Ag distances are also elucidated through variable-temperature single-crystal X-ray crystal structure (VT-SCXRD) analyses.

The title compound, C12H13NO3, was prepared by the nucleophilic substitution reaction of acryloyl chloride with glycylglycine. In the crystal structure, intermolecular N—H...O, O–H...O and C—H...O hydrogen bonds link the molecules into a three-dimensional network.

The asymmetric unit of the title compound, C(15)H(24)O(4), contains one half-mol-ecule; a twofold rotation axis passes through the central C atom. The non-planar six- and five-membered rings adopt chair and envelope conformations, respectively. In the crystal structure, inter-molecular C-H⋯O hydrogen bonds link the mol-ecules.

In the title compound, C12H11N2+·I−, the aromatic rings are oriented at a dihedral angle of 73.40 (3)°. In the crystal structure, π–π contacts between the pyridine rings and the benzene and pyridine rings [centroid–centroid distances = 3.548 (3) and 4.211 (3) Å] may stabilize the structure.

The title compound [systematic name: 2-(2-acrylamido­acetamido)­acetic acid monohydrate], C7H10N2O4·H2O, was prepared by the nucleophilic substitution reaction of acryloyl chloride with glycylglycine. Excluding H atoms, the main chain of the mol­ecule is nearly planar. In the crystal structure, O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network.