Combined multiple pulse NMR and sample spinning techniques have been used to obtain the carboxylic acid1H chemical shift tensor in 2,6hyphen;dimethylbenzoic acid. The values obtained were sgr;perp;=minus;18.5 ppm and sgr;par;=minus;4.2 ppm relative to TMS. A discussion of the changes in line shape of chemical shift tensors under sample rotation is given. This leads to a quantitative expression for the sample rotation speed, ohgr;rGt;sgr;zzminus;1/3Trsgr;, to define rsquo;rsquo;rapidrsquo;rsquo; sample rotation.
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