It is known that lowering the pH by adding strong acids such as HCl leads to longer rods. Conversely, as shown in Fig. , comparing syntheses from the seven-precursor set and seven-precursor plus acid did not show a significantly different distribution of aspect ratios, although the concentrations of acid are mostly considerable ([HCl]=0.001-0.08 M). Specificaly, we observed comparable distribution of ARs in the region of log[AgNO 3 ] between -4.05 and -4.0 for recipes with HCl (ranging from a 2.0 to 5.2, with an average of 3.71) and those without HCl (from 2.0 to 5.0 and an average of 3.58). We note that in our dataset, similar or apparently identical recipes result in different reported aspect ratio. We identified five groups of recipes each with identical concentrations of all seven precursors and relative seed solution amount to the growth solution, but with significantly different ARs (by more than and those are highlighted in blue circles in Fig. which implies there might be other highly significant factors than precursor amounts that impacts the synthesis outcome. This large variance in the aspect ratio can also originate in the measurement of aspect ratio; in particular, the specific sample of nanorods used to obtain the sample distribution for the aspect ratios. Such sampling is sometimes mentioned (e.g., that the researchers sampled > 50 rods in TEM image) but not always.