The relaxation dynamics of spin I=1 nuclei with a static quadrupolar coupling and a radio-frequency field

van der Maarel, J. R. C.
October 1993
Journal of Chemical Physics;10/15/1993, Vol. 99 Issue 8, p5646
Academic Journal
The dynamics of spin I=1 nuclei in a radio-frequency (rf) field and with both a static and fluctuating quadrupolar interaction are discussed. Approximate expressions of the relaxation rates are derived under the assumption that the linewidths are much smaller than the characteristic line-splittings. The conventional spin-lock relaxation rate increases with increasing ratio of the spin-lock field strength and static quadrupolar coupling ω1/ωQ and is sensitive to the spectral density at frequency [Square_Root]ω2Q+4ω21. The rate shows a maximum in the presence of low frequency molecular motion. Some experiments are performed on a deuterium spin probe in a low molecular weight liquid crystal. The creation of multipolar states by continuous rf irradiation is demonstrated.


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