Brrr.
This is our calibration reaction. We believe we understand it pretty well, as the collected literature here suggests. Recently, we have studied it in our High Pressure Flow System at temperatures down to 190K, with the results shown as black circles (earlier work on the HPFS at elevated temperatures is shown as gray hexagons). The data (both high and low temperature data from the HPFS) are fit to a modified Arrhenius form, k = AT^2e(-E/T); the fit is shown, and the lower plot shows fractional residuals of all studies to this fit. Overall, the agreement is quite good. In addition, it appears that T^2 is a little too curved -- we shall soon refit the data, including other investigations, to a T^n form. These are first cut results, and, as such, are very encouraging indeed. Great work, Jesse and Jim!