| Résumé | The NMR spin–lattice relaxation time (T1), spin–spin relaxation time (T2) and the diffusion coefficient D were measured for 1H in a 1:17 mol % solution of tetrahydrofuran (THF) in D2O. The aim of the work was to clarify some earlier points raised regarding the utility of these measurements to convey structural information on hydrate formation and reformation. A number of irregularities in T1 and T2 measurements during hydrate processes reported earlier are explained in terms of the presence of interfaces and possible temperature gradients. We observe that T1 and T2 in solution are exactly the same before and after hydrate formation, thus confirming that the solution is isotropic. This is inconsistent with the presence of memory effects, at least those that may affect the dynamics to which T1 and T2 are sensitive. The measurement of the diffusion coefficient for a number of hours in the subcooled solution before nucleation proved invariant with time, again suggesting that the solution remains isotropic without affecting the guest dynamics and diffusion. |
|---|
