Lithium dynamics in layered Li2TiO3 were characterized by using a combination of 6,7Li nuclear magnetic resonance at 150 to 500K and molecular dynamics simulations. The 7Li static nuclear magnetic resonance and stimulated echo experiments revealed slow and partial lithium diffusion in Li2TiO3. The high-field (21.1T) 6Li magic-angle spinning nuclear magnetic resonance revealed a tetrahedral lithium site, together with the three crystallographic octahedral sites in Li2TiO3. Molecular dynamics simulations predicted that lithium could occupy a tetrahedral site if two or more vacancies existed in the vicinity. This could result from, for example, the presence of a Ti defect in the LiTi2 layer. The 6Li two-dimensional exchange nuclear magnetic resonance experiments revealed evidence of lithium diffusion between the pure Li and LiTi2 layers along the c-axis. Although the two-dimensional exchange nuclear magnetic resonance data were not sensitive to lithium diffusion in the ab-plane, molecular dynamics simulations showed that lithium diffusion in the pure Li layer was equally probable.

Combined 6,7Li NMR and Molecular Dynamics Study of Li Diffusion in Li2TiO3. Vijayakumar, M., Kerisit, S., Yang, Z., Graff, G.L., Liu, J., Sears, J.A., Burton, S.D., Rosso, K.M., Hu, J.: Journal of Physical Chemistry C, 2009, 113[46], 20108-16