Diffusion coefficients in molecular simulation trajectories are quantified using the Einstein's relation. The trajectories are aligned to the central cellulose microfibril, eliminating drift during system equilibration. The error bars for the diffusion coefficients visualize standard error, obtained by splicing the trajectory into nineteen 50 ns segments and quantifying the standard error across these segments. However, as different cell wall components move independently, we find that different approaches are required to determine accurate diffusion coefficients from independent samples. Diffusion Coefficient of H 2 O The diffusion coefficient of water is derived from the linear fit between mean squared displacement and time, as there are many water molecules present in the molecular simulation system, and the mean squared displacement grows linearly with time. The squared displacements of water molecules are computed by analyzing the unwrapped trajectory for each acetylation index, where the change in displacement of the water molecule is calculated relative to the first simulation frame post equilibration period. These squared displacements are thereafter averaged to quantify the mean squared displacement (MSD) as shown in Eq. 3, wherein the t ref refers to the time point at 50 ns.