FIGURE 8.

(A) Series of transient transmission (ΔT) traces of MbCN at five different excitation wavelengths. As the excitation wavelength approaches 400 nm there is a sharp decrease of the transmitted signal on the picosecond scale that corresponds to transient absorption in this region. (B) Longer timescale transient transmission of MbCN recorded at 433 nm. The experimental signal has been normalized and the data corresponding to the first 100 fs have been removed to eliminate contamination from coherent coupling signals. Fitting the remaining data with a sum of three exponentially decaying processes results in time constants of 0.2 ps, 1.2 ps, and 4 ps.