We confirmed this hypothesis by fitting dynamics traces at various frequencies into a biexponential decay. We fit a fast decay with (𝑘 1 + 𝑘 3 ) -1 = 5.6 ps and a long-lived decay with 𝑘 4 -1 = 90.0 ps regardless of the probing frequency (Figure ). The conclusion is further supported by a global analysis (See Supplemental Figure ): if we decompose the spectra into two spectral/dynamical components, both components exhibit identical spectra features. The results, therefore, indicate only a single spectral component exists with a biexponential decay, agreeing with our kinetic model.