Survival of Nuclear Coherences for a Series of Internal Conversions in Free Base Tetraphenylporphyrin

Abstract

We observe that the stepwise internal conversions from B to Q(y) and to Q(x) states in free base tetraphenylporphyrin generate coherent nuclear wave packets in both Q(x) and Q(y) states. Theory and experiment show that these wave-packet motions involve out-of-plane vibrations of the porphyrin ring that are strongly coupled to the internal conversions.