A picosecond regular reflection polarization spectroscopic study on ultrafast photothermal conversion dynamics and energy migration of amorphous Cu-phthalocyanine solid

For the amorphous pellet of Cu-phthalocyanine with bulky substituents photoexcitation energy relaxation processes and their polarization-dependent dynamics were measured and analyzed by picosecond regular reflection spectroscopy. The triplet state (T1) decayed upon T1-T1 annihilation, and the vibrationally hot ground state was produced by ultrafast photothermal conversion via the annihilation. On the basis of depolarization dynamics, the migration of the T1 state is conducted to occur sligthly in 20 ps and the annihilation takes place in molecules of the close vicinity.