This rescaling method factors out sources of systematic uncertainty such as errors in the gasphase reactant flowrates. Furthermore, it allows the new results to be quantitatively compared with a database that contains measured YSIs for hundreds of organic compounds . The parameters YSITOL and YSIHEP are constants that define the YSI scale; their values-170.9 and 36.0-were taken from the database so that the newly measured YSIs would be on the same scale for a direct comparison. SI B lists the liquid-phase flowrates corresponding to 1000 ppm in the gas-phase for each TS, and the property values used to calculate them. SI C shows a schematic diagram of the LSSR apparatus and SI D gives details of the specific burner . Isooctane was included in each measurement set as an internal standard; SI F shows that the values were consistent over time and agreed with previous measurements. SI G shows that the LSSR signals of several low volatility compounds increased linearly with the dopant mole fraction, which confirms that they vaporized readily and the signal response of the optical apparatus was in a linear regime.