Table 1.

Size and mass fraction of Au and organic in the nanocrystal samples measured by SAXS and TGA.

Measured SAXS Diameter, D (nm)	Thiol	Calculated Thiol Mass Percent (%)	Mass Fraction of Ligand Measured by TGA (%)‡
1.8 ± 0.2	C12H25SH	26 ± 9	27
1.8 ± 0.2	C16H33SH	31 ± 11	33
4.1 ± 0.8	C12H25SH	14 ± 9	21

^‡Quantities extracted from the data in Figure 5. The TGA balance has microgram precision, and the error in this measurement is negligible compared to the error in the calculated thiol mass percent. The thiol footprint on a Au surface was assumed to be 0.16 ± 0.02 nm²/thiol.^{46, 47}