Impact on the steady-state MRI-driven accretion when varying the exponent, p_dis,Exp, of the fixed power-law dust size distribution (Model III). Going from solid light-colored to dark-colored lines, p_dist,Expspans the range from −4.5 to 0.25. Panels a–f show the same quantities as in Fig. 2, but for the model parameters M_⋆ = 1M_⊙, L_⋆ = 2 L_⊙, M_disk = 0.05 M_⋆, f_dg,tot = 10⁻², α_hydro = 10⁻⁴, a_min = 0.1 µm, and a_dist,Max = 1 µm. For comparison, the dashed gray and black lines in panel a now display the steady-state quantity α obtained assuming the limiting case of a mono-disperse population of dust with size a_mono = 0.1 µm and a_mono = 1 µm, respectively.