In-plane jump diffusion of Li inLiC6

Li diffusion in LiC/sub 6/ has been measured by high-resolution neutron spectroscopy both in the ordered phase between 630 and 675 K and in the disordered phase at 720 K. The in-plane diffusion constant D at 660 K is 1 x 10/sup -6/ cm/sup 2//s, which increases to 24 x 10/sup -6/ cm/sup 2//s above T/sub c/. At all temperatures, a jump-type diffusion mechanism was observed, with jump vectors connecting nearest Li-sublattice sites in the ordered phase, but nearest hexagon centers in the disordered phase.