Rotational resonance with multiplehyphen;pulse scaling in solidhyphen;state nuclear magnetic resonance

摘要

Multiplehyphen;pulse techniques are applied to rotational resonance experiments in solidhyphen;state nuclear magnetic resonance. The usual rotational resonance condition is satisfied when an integral multiple of the magichyphen;angle spinning speed equals the difference in isotropic chemical shifts of the two members of a homonuclear spinhyphen;1/2 pair. We show that sequences of rapid periodic radiohyphen;frequency pulses scale and rotate both the Zeeman and dipolendash;dipole Hamiltonians, leading to a modification of the resonance condition and to the introduction of new, singlehyphen; and doublehyphen;quantum, rotational resonances. Experimental results are presented which demonstrate these effects in the spectra of doubly13Chyphen;labeled solids. thinsp;