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A study describes the local structure of new proton conducting ionic liquids (PCIL). Intra- and intermolecular interactions are probed to determine pair correlations between the different components of these systems.

A proton abstraction by the carbonate or a related basic ligand is the basic mechanism involved in the palladium-catalyzed intramolecular arylation, which is normally facilitated by the electron-withdrawing substituents on the aromatic ring. The results show that though the electron-withdrawing substituents are inconsistent with an electrophilic aromatic-substitution mechanism, it has the most important directing effect, when placed ortho to the reacting site.

Proton NMR and simulations are combined to examine the origin of chiral selectivity by a polysaccharide used in a commercial chromatographic stationary phase: amylase tris(3,5-dimethylphenylcarbamate). 2D NOESY spectra showed which protons of each enantiomer and the polysaccharide were in proximity, and revealed folding of the L-enantiomer.

High-accuracy distance measurement between remote methyls in specifically protonated proteins is studied. It is shown that [super 1]H-[super 1]H NOEs over distances of up to 12 Angstrom can be feasibly observed using a highly deuterated protein in which protons are selectively incorporated into [delta.sub.1]-methyl sites.

A detailed study of water in Nafion membranes ranging from essentially dry to fully hydrated Nafion using both linear and nonlinear-infrared spectroscopy of the OD stretching mode of dilute HOD in [H.sub.2]O is presented. An understanding of the dynamics of water in Nafion membranes would help in optimizing their function in the application of Nafions membranes in fuel cells, which depends on the internal water for proton conduction.

The binding position and the electronic properties of acidic proton in anhydrous dodecatungstophosphoric acid, H3PW12O40 are studied by means of (super 1)H, (super 31)P spin, echo double resonance (SEDOR) NMR techniques. (super 1)H broad line NMR spectrum showed a bell-type resonance line shape with 4.7 kHz line width and magic angle sample spinning (MAS) NMR spectrum has a single resonance peak, suggesting that the hetero-polyanion PW12O40(super 3-) provides a single site to the acidic proton.