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UV-vis light converts Ag(DM)2 (DM = 2,5-dimethyl- N,N-dicyanoquionediimine; DMe-DCNQI) to several solids with metallic, semiconducting, or insulating conductivities depending on the irradiation conditions. Ag valence state in each photochemical product was determined by Ag L3-edge XANES. The XANES result requires the correction of the redox mechanism to explain the photoinduced conductivity change of Ag(DM) 2 photoproducts. [ABSTRACT FROM AUTHOR]

We investigated local structures around cadmium (Cd) sorbed on montmorillonite at various pH values by EXAFS (extend X-ray absorption fine structure). We found two sorption types, an outer-sphere complex and a surface precipitate. The outer-sphere complex was mainly formed at a lower pH which had an identical structure to aqueous Cd2+, while the surface precipitate was found at high pH which had a one-layer Cd5(OH)8(NO3)2 (H2O)2-like structure. [ABSTRACT FROM AUTHOR]

The first clear atomic-scale images of a Ni2P(0001) surface have been obtained by means of a scanning tunneling (STM) microscope. The STM image shows an ordered hexagonal symmetry of the (0001) face, which can be assigned to phosphorus atoms on Ni3P1- and Ni3P2-terminated surface. The high temperature annealing is crucial to get a well-ordered atomic structure. [ABSTRACT FROM AUTHOR]

We have measured a frequency shift of the noncontact atomic force microsocpy (NC-AFM) cantilever above Au islands when we scanned the X-ray energy around the Au L3 absorption edge. We have found a clear peak of the frequency shift just above the Au L3 absorption edge. This novel phenomenon suggested that the combination of energy-variable X-rays and NC-AFM provides us a new way of nano level chemical mapping of surfaces. [ABSTRACT FROM AUTHOR]

We have carried out ethanol conversion reactions on the MoO3 under the pulse infrared irradiations (period = 2 s) with several wavelengths emitted from free-electron-laser. We found a piece of evidence to show the dependence of activities in the ethanol conversion rate on the infrared wavelengths. When the wavelength was tuned to 967 cm-1, which corresponded to the absorption frequency of 0.167 nm Mo=O bond, C2H5OH was converted mainly to C2H4 with CH3CHO as a minor product while no reaction occurred at 1200 cm-1 where no resonant vibration mode of MoO3 was present. The reaction products were different from those produced in thermal reactions. [ABSTRACT FROM AUTHOR]

Local structure around Ni in a nickel phosphide catalyst supported on K-USY was investigated by an in situ X-ray absorption fine structure (XAFS) method during the reduction process of the catalyst and the hydrodesulfurization (HDS) reaction of thiophene. In the passivated sample, Ni phosphide was partially oxidized but after the reduction, 1.1 nm diameter Ni[sub2]P particles were formed with Ni-P and Ni-Ni distances at 0.218 and 0.261 nm, respectively, corresponding to those of bulk Ni[sub2]P. In situ XAFS clearly revealed that the Ni[sub2]P structure was stable under reaction conditions and was an active structure for the HDS process. [ABSTRACT FROM AUTHOR]