Chemical Physics Letters, Vol.346, No.1-2, 41-46, 2001
Dynamics of a photo-excited state in polydiacetylene studied by femtosecond mid-infrared absorption spectroscopy
Relaxation dynamics of polydiacetylene was investigated with femtosecond time-resolved absorption spectroscopy between 1120 and 1280 cm(-1). A new photo-induced IR band was found at 1225 cm(-1) just after photo-excitation, and it disappeared with a decay time constant of 4.1 +/- 0.7 ps. This IR band is assigned to the vibrational mode which induces self-trapping of the 1B(1u) exciton.