Diffusion parameters in single-crystalline Li3N as probed by 6Li and 7Li spin-alignment echo NMR spectroscopy in comparison with results from 8Li β-radiation detected NMR

6Li and 7Li two-time spin-alignment echo NMR correlation functions of single-crystalline Li3N are recorded. Around room temperature, the decay of the spin-alignment echo amplitudes is induced by slow Li jumps perpendicular to the Li2N layers. The hopping correlation functions can be best represented by a single exponential. The measured jump rates are consistent with those which were previously determined by 8Li β-radiation detected NMR at much lower temperatures. Taking the results from 6Li and 7Li NMR as well as from 8Li β-NMR together, between 360 and 220 K Arrhenius behaviour is found. The corresponding activation energy is 0.65(1) eV and the pre-exponential factor turned out to be 6.4(5) x 1013 s-1. Although probed from a microscopic point of view, the NMR diffusion parameters are in very good agreement with those obtained from dc-conductivity measurements, being sensitive to macroscopic transport properties. (fast track communication)