Figure shows an initial survey of these PNPls suspended in hexane, varying their concentrations from 1 to 80 mg/mL, along with the scattering data of their solid samples for comparison. Figure and show that neither sample Br-170, nor I-110, present any signal of stacking in suspension in hexane for this concentration window (gray dashed lines added for visual aid). Even the most concentrated samples did not show any evidence of stacking. This result reaffirms the great solvation ability of hexane for oleylammonium-capped PNPls. This observation is also of critical importance to the interpretation of FRET in more diluted suspensions, since it suggests that, because the PNPls are further apart from one another, the occurrence of FRET is less probable. For instance, in samples with 1 mg/mL, the average distance between the PNPls would be approximately 120 nm, making FRET unlikely in this case. To further evaluate the hexane solvation in PNPls suspensions, we varied the temperature of the 80-mg/mL samples from 30 to 5 °C, and we performed a hysteresis test, raising back the temperature from 5 to 30 °C with the same intervals. The resulting curves are shown in Figure and. Again, no obvious stacking signal can be observed in these scattering curves upon decreasing the temperature; however, a careful look in Figure (I-110 sample), in the curves from 5 to 30 °C (middle to bottom), reveals discrete undulations between 0.1 and 0.3 Å -1 (gray dashed lines) in the same position of the diffractions 1 and 2 in Figure .