Spin-tickling experiment

The method of tracing coupling interactions by spin-tickling experiments is based essentially on difference spectra, which are generated either by the subtraction of a SPT spectrum from a unperturbed eontrol spectrum or by the type of pulse sequence used in the SPT experiment. With the latter approach only the signals effected by the SPT experiment appear in the difference spectrum. 

The geminal proton-proton coupling constant in a-chloroacrylo-nitrile is both solvent and temperature dependent.Hetero-nuclear spin tickling experiments were used to show that the sign of the geminal coupling constant is of opposite sign to that of... 

Consider first the spin-decoupling experiment (see Fig. 5A) provided that the decoupling field is positioned at the correct frequency and its power is suificiently high, the A-doublet will be detected by the observing radio-frequency as a spin-decoupled singlet. In the case of the spin-tickling" experiment (see Fig. 5B), a much weaker... 

On the other hand, it is possible, by means of a series of spin-tickling experiments, to determine the precise positions of all of the individual transitions and thereby obtain both the chemical shift and all of the coupling constants of the hidden resonance. Unfortunately, the correct positioning " of the rather weak irradiating field required for spin-tickling experiments is both tedious and time-consuming. 

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