Dipolar signals after the JB experiment and Zeeman signals (dotted) in (a) nematic 5CB and (b) powder adamantane, at and . In (a), dipolar (solid) corresponds to a preparation time and dipolar (dashed) to . In (b), several dipolar signals corresponding to different . Vertical lines indicate the times of maximum and zero -order.
Radio frequency pulse sequence used to encode coherences of the spin states at time after the JB pulse pair, on the and bases. Phases and were incremented from zero to in steps of to encode up to eight quantum coherence in both bases. is set short enough to minimize evolution during this period. Setting before the last 45° readout pulse sufficiently long, undesired transient signals are allowed to decay. The signal corresponds to 5CB prepared in a state of dipolar order, , , and .
and basis correlated coherence numbers at short evolution times after the JB pulse pair before the establishment of the quasiequilibrium states in (a) powder adamantane, (b) nematic 5CB prepared in the condition, and (c) 5CB prepared in the condition.
Evolution of the coherence amplitudes for times after the JB pulse pair projected on and bases. (a) Powder adamantane, (b) 5CB prepared in the condition, (c) 5CB in the condition, and (d) same as (c) in the range of .
and basis projections of the coherence spectra [(a) and (b)] at and (c) at . Powder adamantane (a) and 5CB in the state (b) have similar shapes, while 5CB in the state (c) show a completely different composition.
Relaxation of the MQ coherences encoded on the basis, starting from dipolar order in (a) powder adamantane , (b) 5CB condition , and (c) 5CB condition , at and . Inset in (b) shows relaxation of coherence observed in 5CB under the condition.
Dipolar relaxation time vs coherence numbers in powder adamantane (solid diamond), 5CB (solid circle), and (open circle) order at and .
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