M. Grottel et al., H-1 AND F-19 NMR-STUDY OF CATION AND ANION MOTIONS IN GUANIDINIUM HEXAFLUOROZIRCONATE, Zeitschrift fur Naturforschung. A, A journal of physical sciences, 51(9), 1996, pp. 991-996
Proton and fluorine NMR second moments and spin-lattice relaxation tim
es of polycrystalline guanidinium hexafluorozirconate and its deuterat
ed analogue were studied in laboratory (60 MHz) and rotating (H-1 = 20
G) frames over a wide range of temperature. An analysis of the experi
mental results enabled us to reveal a dynamical inequivalence of two c
rystallographically independent cations and an unexpected high mobilit
y of nonspherical anion dimers. A comparison of the ions dynamics in 2
:1 complex studied with the guanidinium 1:1 and 3:1 complexes has show
n a significant contribution of the hydrogen bonds to the potential ba
rriers hindering the anion reorientations. At low temperatures a proto
n motion in the hydrogen bond and at 400 K a solid-solid phase transit
ion have been discerned.