Magnesium metal is an ideal rechargeable battery anode material because of its high volumetric energy density, high negative reduction potential and natural abundance. Coupling Mg with high capacity, low-cost cathode materials such as electrophilic sulphur is only possible with a non-nucleophilic electrolyte. Here we show how the crystallization of the electrochemically active species formed from the reaction between hexamethyldisilazide magnesium chloride and aluminum trichloride enables the synthesis of a non-nucleophilic electrolyte. Furthermore, crystallization was essential in the identification of the electroactive species, [Mg2(μ-Cl)3·6THF]+, and vital to improvements in the voltage stability and coulombic efficiency of the electrolyte. X-ray photoelectron spectroscopy analysis of the sulphur electrode confirmed that the electrochemical conversion between sulphur and magnesium sulfide can be successfully performed using this electrolyte.

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Surface interaction of gold nanoparticles with solvents and functionalized organic molecules is probed using the changes in the surface plasmon absorption band. A red shift in the surface plasmon band is observed with increase in solvent dielectric constant for solvents that do not complex with metal surface. A plot of the square of the observed position of the surface plasmon bands of Au nanoparticles in these solvents as a function of medium dielectric function shows a linear dependence. Interestingly, the surface plasmon band position remains unaffected in polar solvents (with nonbonding electrons) and is attributed to the direct interaction of these solvents with the gold surface. Binding of gold nanoparticles with organic molecules containing functional groups such as -SCN or -NH2 were found to dampen the surface plasmon bands. Binding of phenyl isothiocynate (PITC) and 15 N-labeled benzylamine to gold nanoparticles was probed using NMR techniques, and in both cases, two sets of signals were observed, one from the free molecules and the other from the molecules complexed to Au nanoparticles. Surface binding with organic molecule facilitates the formation of ordered array of gold nanoparticles.

High-resolution (13)C NMR spectra (150 MHz) have been obtained on the complete series of D-aldohexoses (D-allose 1, D-altrose 2, D-galactose 3, D-glucose 4, D-gulose 5, D-idose 6, D-mannose 7, D-talose 8) selectively labeled with (13)C at C1 in order to detect and quantify the percentages of acyclic forms, and to measure and/or confirm percentages of furanoses and pyranoses, in aqueous solution. Aldehyde and hydrate signals were detected for all aldohexoses, and percentages of these forms at 30 degrees C ranged from 0.006 to 0.7% (hydrate) and 0.0032 to 0.09% (aldehyde). Aldehyde percentages are largest for the altro, ido, and talo configurations, ranging from 0.01 to 0.09%; the ido configuration yielded the most hydrate (0.74%). Hydrate/aldehyde ratios vary with aldohexose configuration, ranging from 1.5 to 13, with gluco exhibiting the smallest ratio and gulo the largest. (2)H Equilibrium isotope effects (EIEs) on aldohexose anomerization were measured in D-galactose 3 and D-talose 8 selectively (13)C- and (2)H-labeled at C1 and H1. The (2)H isotope effect on (13)C chemical shift, and broadband (1)H- and (2)H-decoupling, were exploited to permit simultaneous observation and quantitation of the protonated and deuterated molecules in NMR samples containing equimolar mixtures of D-[1-(13)C]aldose and D-[1-(13)C; 1-(2)H]aldose. Small (2)H EIEs were observed for 8, but were undetectable for 3. These results suggest that configuration at C2 influences the magnitude of the (2)H isotope effect at H1 and/or that the observed effect cannot be reliably interpreted due to complications arising from the involvement of acyclic aldehyde forms as intermediates in the interconversion of cyclic forms. The observed (2)H isotope effects on aldohexose tautomeric equilibria provide new insights into the important question of whether (2)H substitutions can alter aldofuranose ring conformation, and lead to the identification of an optimal (2)H- and (13)C-substituted 2-deoxyribofuranose isotopomer on which to investigate this potential effect.