Fig. 2. (a) IR absorption and (b) 2D-IR spectrum of pure serum in the amide I region. Arrows identify two components of the v = 0–1 transition discussed in the text. (c) IR pump–probe spectrum of H2O at a pump–probe time delay of 300 fs. (d) 2D-IR spectrum of H2O, magnified 50×. The spectra in (b) and (d) were both obtained with a waiting time (Tw) of 250 fs and are plotted on the same scale, see colour bar.
