These signals are consistent with those of TIPS-Tn S 1 excitons measured previously. As with TIPS-Pn, the averaged and normalized 0.05 mM TA data show minimal shape change over 8 ns (Fig. )), indicating that this spectrum predominantly contains singlet excitons, with minimal SF, ISC, or excimer formation. The decay of the spectrum fits well to a single exponential with a 12.7 ± 0.2 ns time constant (Sec. S5.1 of the supplementary material). This time constant is reasonably consistent with the 13.2 ns singlet lifetime of TIPS-Tn in anhydrous toluene previously reported by and the 11.6 ns lifetime in chloroform reported by In contrast, the 8 mM TIPS-Tn TA spectrum shows some shape change over time (Fig. ).