Figure 2.

(A) Normalized short-time cage diffusion D_cage^′ = D_s(q*)/D₀ as a function of the volume fraction ϕ. Results for the hard (HE) and attractive (ATT_E) ellipsoids are displayed, together with results for the hard (HS) and attractive (ATT_S) spheres.²³ Inset: short-time cage diffusion as a collective effect characterizes the dynamical relaxation of structural correlations between neighboring particles. (B) The nonmonotonic contribution to the crowding effect due to a nonspherical shape can be clearly seen from the normalized difference between short-time cage diffusion of ellipsoids and spheres, as obtained from theoretical predictions for hard spheres⁴³ (solid black line in panel A) and polynomial guide-to-the-eyes (dashed lines in panel A).