Regensburg 2004 – wissenschaftliches Programm
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DF: Dielektrische Festkörper
DF 5: Poster
DF 5.12: Poster
Mittwoch, 10. März 2004, 14:30–18:00, Poster C
Studies on local structure and Li diffusion in LiAlO2 single crystals using 7Li and 27Al NMR spectroscopy — •Sylvio Indris1, Daniel Albrecht1, Paul Heitjans1, and Reinhard Uecker2 — 1Institut für Physikalische Chemie und Elektrochemie, Universität Hannover, 30167 Hannover, Germany — 2Institut für Kristallzüchtung, 12489 Berlin, Germany
We studied the local structure of LiAlO2 single crystals by 7Li and 27Al NMR spectroscopy. Lineshape measurements with different orientations of the crystals with respect to the magnetic field give the possibility to probe the electric field gradients at the sites of the Li and Al ions, respectively, and thus yield information about the local symmetry of these sites. The dynamics of the Li ions was studied via the temperature dependence of the 7Li NMR lineshapes and 7Li spin-lattice relaxation times T1. These measurements were done at temperatures between 300 K and 1000 K and for different crystallographic orientations. The results are discussed with respect to the hopping rate of the Li ions and the activation barriers for single ion jumps and are compared with results from conductivity measurements and quantum chemical calculations.