(2.7 ± 0.6) × 10 9 M -1 s -1 to (2.5 ± 0.6) × 10 9 M -1 s -1 , and the 8 mM SF triplet yield from 20-31% to 19-29%. ISC could potentially affect the triplet yield even at 20 mM, where the contribution to triplet formation is 3.5%. Dvořák et al. quantified the rate of SF in solution for TIPS-Pn concentrations ranging from 5-60 mM, but did not account for ISC. It is possible that for the lowest concentrations used, a portion the SF observed was actually due ISC, and the SF rates may be overestimated.