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The charge dependence of surface plasma resonance (SPR) on 2 nm octanethiol-protected Au nanoparticles is investigated. The result revealed a shift in the SPR peak position and stated that the variation in the corresponding line width as a function of charge can be well rationalized in a quantitative and self-consistent way by simple free-electron based Mei theory.

The first combined application of solid-state electrochemical NMR (EC NMR), cyclic voltammetry (CV) and potentiostatic current generation is reported. This is done in order to investigate the topic of ruthenium promotion of MeOH electro-oxidation over nanoscale platinum catalysts.

Spatially resolved quantitative analysis of the local distribution of Pt in carbon-supported PtRu nanoparticles (NPs) is described by using the RKKY (Ruderman-Kittel-Kasuya-Yosid) J coupling measurements by in situ [super 195]Pt electrochemical NMR (EC-NMR). This method can be applied to other Pt-based alloy NPs and can also be used for understanding the catalytic actions of a given Pt-based alloy NP catalyst.

The observation of Selenium-77 nuclear magnetic resonance (NMR) in octaneselenol-protected gold nanoparticles is presented. The selenium-77 NMR suggests the presence of conducting electrons at the Se atom, spilled over from the metal nanoparticles.

The Co tolerance of Pt/Ru fuel cell materials was studied by analyzing nuclear magnetic resonance data from platinum-195 in commercial, graphite-supported (Vulcan) nanoscale platinum electrodes in an electrochemical environment. Findings showed a major enhancement of s-like local density of states at the Fermi level at the electrode surface under wet conditions. This was indicated by the increase in Ruderman-Kittel-Kasuya-Yosida J coupling and a low-field shift of the surface peak consistent with a lowered surface potential in the electrolyte.

Presents a detailed nuclear magnetic resonance (NMR) model for carbon monoxide. Use of the 13C NMR shift and spin-lattice relaxation measurements; Temperature dependence of the 13C spin-lattice relaxation rate; Two-band model developed for ligand 13C atoms.

Surface attachment of the manganese-oxo cluster known as Mn-12 provided aqueous solution stabilization that allowed investigation of the use of the cluster as an MRI contrast agent. [ABSTRACT FROM AUTHOR]

Surface attachment of the manganese–oxo cluster known as Mn-12 provided aqueous solution stabilization that allowed investigation of the use of the cluster as an MRI contrast agent. [ABSTRACT FROM AUTHOR]

Three octanethiol-protected Au nanoparticle samples having average particle sizes of 1.7, 2.1 and 2.8 nm, respectively are synthesized and characterized by electrochemical differential pulse voltammetry (DPV) and 1H-/13C-NMR. The potentials of zero charge, Epzc, of the Au nanoparticles are found to be particle size dependent. They are −0.654, −0.449 and −0.203 V (w.r.t the Ag ∣ AgCl ∣ 3 M Cl− reference electrode) as the particle size increases from 1.7 to 2.1 and to 2.8 nm, reflecting a change in the work function of the systems. However, based on the particle double-layer capacitances measured by DPV and the particle sizes by transmission electronic microscopy, the converging value of the dielectric constant, ϵ, of the protecting octanethiol layer is found to be 3.2±0.3. On the other hand, the 1H-/13C-NMR characterization shows that the significant line broadening observed for the nuclear magnetic resonance (NMR) lines of the C3–C8 carbons and the associated protons, once the octanethiols are bound to the metal surface, is mainly due to the reduction in motion of the species. In addition, the large particle size dependent down-field shift observed for the NMR signal from the 13C-labeled α-carbon indicates an underlying electronic metal-ligand bonding mechanism for the shift and the width of the corresponding peak, in accordance with the Epzc versus particle size relationship. [Copyright &y& Elsevier]