Spin antiechoes in liquid-crystalline samples

Abstract The one-dimensional echo spectrum suggested by A. Bax, A. F. Mehlkopf and J. Smidt ( J. Magn. Reson. 35 , 167), given here the name antiecho, and which is designed to produce homonuclear decoupled spectra, is applied to some examples of spectra from molecules dissolved in liquid-crystalline solvents. It is shown that virtually complete homonuclear decoupling is achieved for cases where the ratio of chemical shifts to dipolar coupling is greater than about 2:1. A more complex antiecho is obtained from more strongly coupled spins, but analysis of such spectra is possible and is demonstrated to yield useful spectral parameters.