Time mean squared vertical gas velocity at the midplane, ${\langle v_{z,\text{gas}}^2\rangle |}_{\text{mid}}$, vs. time mean dimensionless dust vertical diffusion coefficient, 〈α_diff〉, with different values of R for runs of diffusion cases in dynamic-dust simulations. The symbols correspond to runs with (Z_D2G, a) = (0.003, 10 μm) (circles), (0.01, 10 μm) (triangles), (0.03, 10 μm) (crosses), (0.1, 10 μm) (squares), (0.03, 30 μm) (pentagons), and (0.1, 30 μm) (stars). The dotted lines show Eq. (C.1) with τ_corr Ω_K = 0.1, 1.0, and 10.0.