The elimination of degeneracies in spin systems of magnetically equivalent nuclei by nematic solvents and spin tickling

Publisher Website
Google Scholar
Abstract
Unique new observables for spin systems composed of magnetically equivalent nuclei can be obtained by dissolving symmetric molecules in nematic solvents and then utilizing nuclear magnetic double resonance techniques. Proper manipulation of both the decoupling radiofrequency and the observing FT pulses allows one to prepare the spin system so that a degenerate transition can be separated into its component parts. These techniques are exhibited for the AX2 spin system and can be expected to be very useful in the study of relaxation in more complex coupled systems, such as A3, AX3, A2X2, etc. Also, different relaxation rates for the singlet and triplet transitions can be observed for these two components of the central line. The nonexponential behavior of this particular combination line in the absence of tickling is thereby readily explained.