Figure 3.

(a) fs‐transient absorption spectra of K,Na‐PHI measured at selected time delays after excitation at 330 nm, ≈72 μJ cm⁻² per pulse: the spectra were smoothed by adjacent‐averaging method to reduce high‐frequency noise from scattering (the original data are shown in the Figure S9a). The fs‐transient absorption data were recorded at increased concentration (5 g L⁻¹) compared to the ns‐TA data to improve the S/N of the data. (b) Decay kinetics at selected wavelengths and the insert shows their corresponding normalized decay curves (c) ns‐transient absorption spectra of K,Na‐PHI recorded at selected time upon 355 nm excitation and (d) its decay kinetics at selected wavelengths, inset: their corresponding normalized decay curves.