Lifetimes are displayed above each peak. All lifetimes are from pump-probe measurements using the 193 nm probe with 8 ns pulses. The only exception is the 1429 ps lifetime, obtained using the 213 nm ps probe. Lifetimes were measured at the origin, 32216 cm -1 , and at +214, +511, +984, and +1307 cm -1 , relative to the origin. The letters correspond to peaks with similar pump-probe traces, shown in Figure . shows the 2C-R2PI spectrum of 2,6-dAP (7H). The origin transition is at 32216 cm -1 , which matches well with the origin found by Gengeliczki et al. (32215 cm -1 ).( ) The R2PI spectrum was acquired using 193 nm as the second color. In addition, we acquired the R2PI spectrum for 7H 2,6-dAP using a picosecond ionization at 213 nm, which had similar features, but at worse signal to noise ratio (Fig. ). This latter spectrum is generally more diffuse with no signal beyond 33600 cm -1 . Figs. S4 -S6 show pump-probe spectra; figure shows samples of excited-state decays. The nanosecond decay traces for the origin and +214 cm -1 peaks (denoted with letter a, Fig. ) are similar and both were fit using biexponential functions (Fig. ). To fit these two peaks, we assigned 25 ns and 15000 ns time constants to exponential decay functions. While these fits are not unique, they represent a range of approximately ±25%. The ps pump-probe traces for the +0 and +214 cm -1 peaks show no indication of sub ns decay (Fig. ). The origin decay differs from that measured by Gengeliczki et al. , in which we reported a single 8.7 ns lifetime. In that earlier work we used 266 nm for ionization. Using 193 nm in the current work allows ionization out of lower energy excited states, suggesting that the slow excited-state decay component that was not observed before, corresponds to a lower energy and much longer-lived triplet excited state.