Figure 3.

Lateral diffusion coefficients as as a function of bilayer separation. Diffusion coefficients were calculated from a linear fit to the mean squared displacement as a function of time. A two-dimensional model was used for fitting displacements; this is appropriate for lipid diffusion and water diffusion at low hydration. At full hydration, the water diffusion will be more appropriately fit by a 3D model, but the model error is bounded at 50% (⟨r²⟩ = 6Dt versus 4Dt), while the observed diffusional slowing effect is several orders of magnitude.