The stacks of PNPls show remarkable colloidal stability: upon concentration saturation, they do not precipitate over time. Figure shows curves of a Br-170 hexadecane suspension collected along seven hours, and the scattering peaks from the stacking present similar intensity and width. The analogue curves for the Br-170 suspensions in dodecane and decane are presented in Figure S10. To complete the analysis, we used the Scherrer equation to calculate the approximate size of the PNPls stacks from the first peak of the scattering curves in Figure . We found values variating from ~15 nm (~4 NPls, in hexane) to ~51 nm (~11 NPls, in hexadecane). For a matter of comparison, the dry sample has a stack size of ~64 nm, which corresponds to ~13 NPls.