Fluorine nuclear magnetic resonance line-shape data were collected for a pure LaF3 single crystal and for La1-xSrxF3-x single crystals, doped with admixture concentrations, x, of up to 16%, from room temperature up to 775K. The experimental data were analyzed within the framework of a theoretical model which linked the shape of the spectrum to parameters describing motional processes in the system. The elaborated model included various types of F dynamics: diffusion processes occurring inside 2 distinct F sub-lattices and inter-lattice exchange motion. This theoretical approach provided a satisfactory and consistent interpretation of the nuclear magnetic resonance data, without assuming any distribution of the characteristic time constants. The obtained results were considered within the context of Arrhenius temperature dependences of the correlation times and effects caused by higher concentrations of the admixtures.

Dynamics of Fluorine Ions in LaF3-Type Crystals Investigated by NMR Lineshape Analysis. D.Kruk, O.Lips, P.Gumann, A.Privalov, F.Fujara: Journal of Physics - Condensed Matter, 2006, 18, 1725-41