Spinning sidebands in two-dimensional spin-echo spectra

Two-dimensional Fourier transformation of spin echoes produces a spectrum in 2 frequency dimensions which can have enhanced resolving power. In such spectra 2 sets of anomalous spinning sidebands are obsd., having F1 coordinates equal to 1/2 the spinner frequency. A theor. treatment is presented which accounts for this behavior, showing that the anomalous sidebands are a consequence of the 180 Deg refocusing pulse and that they disappear when this pulse is omitted. "Conventional" spinning sidebands are also obsd., corresponding to modulation at the spinning rate in both time dimensions; they have half the intensity of the anomalous sidebands and are inverted in phase with respect to the center-band signal. [on SciFinder (R)]