1H and 19F spin–lattice relaxation studies for 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide in bulk and mesoporous MCM-41 silica matrix confinement were performed under varying temperatures in a broad range of magnetic fields, corresponding to 1H resonance frequency from 5Hz to 30MHz.A thorough analysis of the relaxation data revealed a three-dimensional translation diffusion of the ions in the bulk liquid and two-dimensional diffusion in the vicinity of the confining walls in the confinement. Parameters describing the translation dynamics were determined and compared. The rotational motion of both kinds of ions in the confinement was described by two correlation times that might be attributed to anisotropic reorientation of these species.

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(1)H nuclear magnetic resonance relaxometry has been applied to reveal information on dynamics and structure of Gu3Bi2I9 ([Gu = C(NH2)3] denotes guanidinium cation). The data have been analyzed in terms of a theory of quadrupole relaxation enhancement, which has been extended here by including effects associated with quadrupole ((14)N) spin relaxation caused by a fast fluctuating component of the electric field gradient tensor. Two motional processes have been identified: a slow one occurring on a timescale of about 8 × 10(-6) s which has turned out to be (almost) temperature independent, and a fast process in the range of 10(-9) s. From the (1)H-(14)N relaxation contribution (that shows "quadrupole peaks") the quadrupole parameters, which are a fingerprint of the arrangement of the anionic network, have been determined. It has been demonstrated that the magnitude of the quadrupole coupling considerably changes with temperature and the changes are not caused by phase transitions. At the same time, it has been shown that there is no evidence of abrupt changes in the cationic dynamics and the anionic substructure upon the phase transitions.

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