The temperature dependence of the calculated tracer diffusion coefficients for the isotopic variants of Li10SnP2S12 (top panel of Figure ) and Li6PS5Cl (bottom panel of Figure ) are consistent with the experimental data. The 7 Li compounds continue to have higher activation barriers, irrespective of the composition and structure. Here, the Li10SnP2S12 compounds were found to have activation barriers of 0.20 eV and 0.25 eV for Li and Li, respectively. The Li6PS5Cl compounds were found to have activation barriers of 0.19 eV and 0.22 eV for Li and Li, respectively. The uncertainty of 𝐸 A in all cases is ±0.02 eV, determined from the variance of the weighted-leastsquares regression of the computational diffusivities.