NMR oxygen-17 studies of the state of water in a saturated sucrose solution

The frequency dependence of the water oxygen-17 transverse and longitudinal relaxation times is used to investigate the dynamic state of water in a saturated sucrose solution at 298K. Assuming that the observed frequency dependence originates from the slow modulation of the residual quadrupole coupling of the water-sucrose interaction, an anisotropic rotation model is used to extract water relational correlation times and the order parameter characterizing the water-sucrose dynamic complex. Although the theory succeeds in providing a quantitative fit to the longitudinal data there is an unexpected anomalous dephasing enhancement in the transverse relaxation, and the paper concludes with a discussion of the possible origins of this enhancement and of alternative models for the dynamic state of the water. (C) 1998 Elsevier Science B.V.