抄録
A conduction mechanism of Li ions in lanthanum lithium tantalate was investigated by 7Li NMR and impedance spectroscopy. Conductivity spectra of La1/3-xLi3xTaO3 exhibited Jonscher′s universal dynamic response behavior. A scaling analysis showed that these conductors are expected to behave as strong electrolytes. Correlation times of lithium motion were estimated from NMR spin-lattice relaxation measurements to be in the order of 10-9 s at room temperature. Activation energies of the correlation times, which correspond to barriers to elementary hops of Li ions, were 8 kJ mol-1 for x=0.06 and 10 kJ mol-1 for x=0.09. These microscopic activation energies were confirmed to relate to those of macroscopic dc conductivities through power-law exponents.
