Ultrafast optical responses of doubly N-confused hexaphyrin derivatives with femtosecond laser excitation

Confused hexaphyrin derivatives were excited by femtosecond pulsed laser to study transient responses. An extended n-conjugated system showed characteristic absorption changes with relatively weak power of laser irradiation. Recovery of transient bleaching was observed with time constants less than 100ps by both 400nm and 800nm excitation. Copper complex derivative showed the fastest response of 21 ps. Optical responses in the visible region and its mechanism are discussed.