Diffusion Coefficient of Other Plant Secondary Cell Wall Components For the remaining components -cell wall biopolymers and ions, the diffusion coefficient were quantified by incorporating a sliding window (∆t = 50 ns).Rather than water, where each molecule can move independently from the others, the tight network of interactions between biopolymers means that the diffusion is coordinated between components. This reduces the number of independent samples, and so Eq. 4 can be non-linear with limited sampling. Therefore, the long trajectories for the components are analyzed over a sliding window of 50 ns trajectory blocks to calculate the diffusion coefficient for a fixed time interval ∆t: