Fig. 4.

Optical properties of molecular bilayer graphenes. a Absorption (solid line) and emission (dashed line) spectra of 1 (blue) and 2 (red). b Time-resolved fluorescence kinetics of 1 (blue, monitored at 767 nm) and 2 (red, monitored at 683 nm). The average lifetime of 1 and 2 is 28.5 and 118 ns. c, d Transient absorption kinetics of c 1 and d 2 monitored at their respective first vibronic peak position