TY - JOUR
T1 - From ultraslow to fast lithium diffusion in the 2D ion conductor Li0.7TiS2 probed directly by stimulated-echo NMR and nuclear magnetic relaxation
AU - Wilkening, M.
AU - Küchler, W.
AU - Heitjans, P.
PY - 2006/8/17
Y1 - 2006/8/17
N2 - Li7 stimulated-echo NMR and classical relaxation NMR techniques are jointly used for the first time for a comprehensive investigation of Li diffusion in layer-structured Li0.7TiS2. One single 2D Li diffusion process was probed over a dynamic range of almost 10 orders of magnitude. So far, this is the largest dynamic range being measured by Li7 NMR spectroscopy directly, i.e., without the help of a specific theoretical model. The jump rates obey a strict Arrhenius law, determined by an activation energy of 0.41(1)eV and a preexponential factor of 6.3(1)×1012s-1, and range between 1×10-1s-1 and 7.8×108s-1 (148-510K). Ultraslow Li jumps in the kHz to sub-Hz range were measured directly by recording Li7 spin-alignment correlation functions. The temperature and, in particular, the frequency dependence of the relaxation rates fully agree with results expected for 2D diffusion.
AB - Li7 stimulated-echo NMR and classical relaxation NMR techniques are jointly used for the first time for a comprehensive investigation of Li diffusion in layer-structured Li0.7TiS2. One single 2D Li diffusion process was probed over a dynamic range of almost 10 orders of magnitude. So far, this is the largest dynamic range being measured by Li7 NMR spectroscopy directly, i.e., without the help of a specific theoretical model. The jump rates obey a strict Arrhenius law, determined by an activation energy of 0.41(1)eV and a preexponential factor of 6.3(1)×1012s-1, and range between 1×10-1s-1 and 7.8×108s-1 (148-510K). Ultraslow Li jumps in the kHz to sub-Hz range were measured directly by recording Li7 spin-alignment correlation functions. The temperature and, in particular, the frequency dependence of the relaxation rates fully agree with results expected for 2D diffusion.
UR - http://www.scopus.com/inward/record.url?scp=33747056611&partnerID=8YFLogxK
U2 - 10.1103/PhysRevLett.97.065901
DO - 10.1103/PhysRevLett.97.065901
M3 - Article
AN - SCOPUS:33747056611
SN - 0031-9007
VL - 97
JO - Physical Review Letters
JF - Physical Review Letters
IS - 6
M1 - 065901
ER -