Transient Exciplex Formation Electron Transfer Mechanism

Figure 13

Dependences of log𝑘_Q (top) and log (1/𝑘_Q−1/𝑘_Diff)) (bottom) on Δ𝐺_ET^∗ for quenching of excited singlet state of thioxanthone by methylbenzenes (triangles) and methoxybenzenes (circles) in MeCN (according to the experimental data of Jacques et al. [39]). Best plots are shown for simulation of the experimental dependence by (3) (𝜆=0.1 and 0.5 eV, resp.) (dash lines) and by concatenated mechanism (16) (solid lines). Dotted line shows thermodynamic limit for ET. Experimental dependence of the exciplex emission frequencies, ℎ𝜈_Ex, on Δ𝐺_ET^∗ in MeCN is shown in the middle panel.