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13C NMR relaxation studies of a 2:1 AlCl3:1-ethyl-3-methylimidazolium chloride (MEICl) melt between 26 and 57 °C provide rotational correlation times for MEI+ which are compared with viscosities and diffusion coefficients. Diffusion coefficients for MEICl in a 2:1 AlCl3−MEICl melt are determined using 1H diffusion ordered spectroscopy (DOSY) between 26 and 57 °C. All MEI+ diffusion coefficients (ring, methyl, and ethyl protons) are virtually identical at a given temperature. The MEI+ diffusion coefficients are viscosity dependent and correlate with conductivity and 13C NMR rotational correlation times, indicating that the transport properties of the 2:1 AlCl3−MEICl melt are determined by the molar quantities of salt and not by the properties of the individual ions. Microviscosity factors provide reasonable values for the radius of MEI+ from both viscosity and 13C NMR rotational correlation times. The “slip” model is used to describe the movement of MEI+ in the 2:1 AlCl3−MEICl melt where Al2Cl7 - is the predominant anion. The ab initio structures of AlCl4 - and Al2Cl7 - have been calculated at the HF/6-31G(d) level.

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The anodic oxidation of a number of unsaturated hydrocarbons at 80°C in 1N H2S04 on a platinized Pt electrode has been studied. The mechanism previously established for the anodic oxidation of ethylene was shown to apply to all unsaturated hydrocarbons studied which involve single or conjugated double bond systems. Essentially the same kinetic parameters were observed for all doublebonded hydrocarbons. The small decrease of reaction rate at constant potential with increasing size and polarizability of the organic was attributed to differences in coverage and to an effect of the organic on the stability of the -OH radicals formed on the surface in the water discharge step, assumed to be the rate-determining step in all these systems. The origin of the observed variation of the current with time at constant potential was shown to be due to diffusion-controlled rate of adsorption of ethylene in the initial stages (up to about 15 min) and then to slow activated adsorption.