C-13 CP MAS SPECTRAL ASSIGNMENT WITH ONE-DIMENSIONAL SEPARATED-LOCAL-FIELD SPECTROSCOPY

A one-dimensional procedure, based upon separated-local-field spectroscopy with magic-angle spinning, is presented that can be used to assign 13C resonance lines in a CP/MAS spectrum on the basis of number of protons attached to carbons. While previous methods have relied upon two-dimensional techniques for this purpose, it is shown that with an optimum choice of the speed of magic-angle sample spinning and the duration for which multiple-pulse proton decoupling is applied, the same could be accomplished in a single experiment, thus saving substantial experimental time. The procedure is illustrated with several examples. © 1991.