Figure 2.

Absorption (solid lines) and emission (dashed lines) spectra of (a) 6-BgCoum (excited at 345 nm), (b) 7-BgCoum (excited at 330 nm), (c) 8-BgCoum (excited at 340 nm),65 and (d) 9-BgCoum (excited at 317 nm).

Absorption (solid lines) and emission (dashed lines) spectra of (a) 6-BgCoum (excited at 345 nm), (b) 7-BgCoum (excited at 330 nm), (c) 8-BgCoum (excited at 340 nm),65 and (d) 9-BgCoum (excited at 317 nm).