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Fluorine substitution in the methylene position strengthens the adjacent C-C bonds and weakens the opposite C=C bond.Fluorine atoms in the vinyl position also strengthen the adjacent C=C and C-C bonds while weakening the opposite C-C bonds.This pattern of the effect of fluorine substitution in cyclopropenes is the same as that found in cyclopropanes and cyclopropenyl cations.20 The qualitative pattern of changes in the C=C stretching frequencies discussed above is partly a force constant (electronic) effect exerted through the F matrix and partly a mass effect exerted through the G matrix. Since the force constants in perfluorocyclopropene have been restored almost to their cyclopropene values, the high frequency of 1940 cm"1 in perfluorocyclopropene is almost all a G matrix effect. The naturally higher frequency of CF stretching in comparison to CC1 or even CC stretching, as in a methyl-substituted cyclopropene, enhances the coupling of C=C and CF stretching frequencies.For chlorine substitution on cyclopropenes only general observations are possible at the present time. Since the C==C and

The yield of complete oxidation product (CO 2 ) from electrocatalysis of methanol on a Pt(100) electrode in perchloric acid electrolyte at room temperature was determined by combined measurements of chronoamperometry and linear sweep voltammetry. The fractional yield of CO 2 was zero over a potential range of 0.35-0.45 V RHE and increased monotonically to unity over the potential range of 0.5-0.65 V. The results may be explained by a simple parallel mechanism, in which methanol oxidizes directly to CO 2 , or by a complex serial mechanism, in which the overpotential for CO oxidation is reduced by solution phase methanol.

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