2D sections of the first component of the flux field J₁ of molecules of increasing gyration radius, with macroscopic concentration gradient 〈−∇c〉 = (1, 0, 0), computed by FFT method on the identified two-scale model of platelets with parameters shown in Table 5. The microstructure volume is 300 × 300 × 300 nm³ (909³ voxels at resolution 0.33 nm per voxel). a) r_g = 0.35 nm, b) r_g = 1.06 nm, c) r_g = 1.77 nm, d) r_g = 2.49 nm.