FIG. 5.

Representative even order experimental multiple spin correlations, obtained in adamanatane for magic echo time τ = 100 µs and evolution time T = 240 µs (see Fig. 2 for definitions of τ and T). We performed 4 signal averages and incremented ϕ from 0 to 4π by π/30 (120 phases ϕ were used). The spectrogram shown in the figure is obtained by a Fourier transform of the echo peak amplitude variation with phase. The growth and subsequent decay of coherence peak amplitudes for adamantane and calcium uoride are plotted in Figs. 8 and 9.