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The structure of nanoparticles plays a critical role in dictating their material properties. Gold is well known to adopt face-centered cubic (fcc) structure. Herein we report the first observation of a body-centered cubic (bcc) gold nanocluster composed of 38 gold atoms protected by 20 adamantanethiolate ligands and two sulfido atoms ([Au38S2(SR)20], where R=C10H15) as revealed by single-crystal X-ray crystallography. This bcc structure is in striking contrast with the fcc structure of bulk gold and conventional Au nanoparticles, as well as the bi-icosahedral structure of [Au38(SCH2CH2Ph)24]. The bcc nanocluster has a distinct HOMO-LUMO gap of ca. 1.5 eV, much larger than the gap (0.9 eV) of the bi-icosahedral [Au38(SCH2CH2Ph)24]. The unique structure of the bcc gold nanocluster may be promising in catalytic applications. [ABSTRACT FROM AUTHOR]

The palladium N-heterocyclic carbene complex trans-[PdCl2{1,3-bis(2,6-diisopropylphenyl)-imidazol-2-ylidene}(NC5H5)] has been prepared and its X-ray molecular structure is reported. The complex is highly catalytically active in the cross-coupling reaction of phenylhalides with phenylthiol to afford diphenyl sulfide and is efficient for the coupling of chlorobenzene. [ABSTRACT FROM AUTHOR]

Highlights: [•] A synthetic method for ultrasmall Pt nanoparticles (∼1nm) is developed. [•] Compared to bulk Pt, structural relaxation is observed in the Pt nanoparticles. [•] The Pt 4f core level energy shifts positively by +1eV compared with bulk Pt. [Copyright &y& Elsevier]

Abstract: Reactions of different alkane-bridged (n =1–3) di-NHC precursors, bisimidazolium chlorides with the NiCl2 in presents of K2CO3 in acetonitrile give the corresponding 16-electron binuclear complexes of the type Ni(di-NHC)(μ-O)2CO in moderate yield. The molecular structures of 1–3 have been determined by X-ray crystallography, which revealed a cis-chelating di-NHC on a slightly distorted square-planar nickel center with κ2-cabonato ligand. The influence of the different di-NHC ligands on the structure and reactivity of the complexes has been studied. The catalytic properties of the complexes were investigated in the Kumada reaction for cross-coupling of phenylmagnesium bromide with a variety of aryl halides. The complex 3 which has the longest linker between two NHCs shows the best catalytic activity in these reactions. [Copyright &y& Elsevier]

Abstract: A series of di-NHC ligands with alkyl bridges of different chain lengths (n =2–4) and their bi-palladium complexes (4, 5 and 6) have been prepared. The molecular structure of 4 and 6 were determined by X-ray diffraction studies. The structures of complex 4 consist of two pseudo-square-planar subunits in a trans configuration, however 6 consist of two subunits in a cis configuration with π–π stacking between two pyridines. The influence of the different bridges on the structure and reactivity of the complexes has been studied. The catalytic activity of the new binuclear palladium complexes was successfully tested in the Mizoroki–Heck reaction of styrene with bromobenzene. The complex with 2 and 4 carbon linker gave higher yield, while the one with 3 carbon linker gave better regioselectivity. [ABSTRACT FROM AUTHOR]

Abstract: CoNb2O6 was prepared by hydrothermal synthesis with polyvinyl alcohol as an additive. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were used to investigate the lattice parameters and the particle morphology. The products were observed as irregular particles with an average particle size of ca. 500nm, which agglomerated from thin slices. Compared with the common columbite CoNb2O6, which was obtained by a traditional solid-state reaction, the product obtained by the hydrothermal method crystallized into a rutile structure. The rutile CoNb2O6 was metastable and it could transform into the columbite structure after calcining at 800°C in air for 4h. [Copyright &y& Elsevier]

Abstract: α-Fe2O3 nanoparticles/TiO2 nanowires hybrid structure is fabricated by two-step hydrothermal treatment. TiO2 nanowires are prepared by heating of titanate nanowires, which are obtained by hydrothermal treatment of TiO2 powder and further repeated HCl treatment. α-Fe2O3 nanoparticles are deposited on the surface of TiO2 nanowires by hydrothermal treatment in Fe(NO3)3 solution. The HRTEM images confirm the junctions between α-Fe2O3 nanoparticles and TiO2 nanowires. The formation of hybrid structures has significant influence on the magnetic properties of α-Fe2O3. The Morin transition temperature of α-Fe2O3 nanoparticles/TiO2 nanowires hybrid structure is 190K, which is determined by the sharp peak in the differential ZFC curve. Whereas there is no observable Morin transition for the corresponding isolated α-Fe2O3 nanoparticles with similar average particles size of ca. 20nm. [Copyright &y& Elsevier]