Figure 5.

Tunable FSRS with a visible Raman pump unveils rich photochemistry. (a) Semilogarithmic contour plot of the Stokes FSRS time-resolved spectra of the GFP-S205V mutant with 539 nm Raman pump up to 900 ps after 400 nm photoexcitation. The ground state FSRS spectrum (blue) is plotted below for comparison. The dispersive line shapes are marked by the dashed lines in between the positive and negative components at ~1218 and 1340 cm⁻¹. (b) The intensity dynamics of the A* 1583 cm⁻¹ mode and I* 622 cm⁻¹ mode in the electronic excited state. The time constants from least-squares fits are listed by the color-coded arrows on characteristic time scales. (c) The frequency dynamics of the 1583 cm⁻¹ mode with the single exponential fit time constant.