Th. Tranthi et al., PICOSECOND RELAXATION OF CHARGE-TRANSFER STATES IN AN ASYMMETRIC CERIUM DOUBLE-DECKER SANDWICH COMPOUND, Chemical physics letters, 213(1-2), 1993, pp. 139-144
Subpicosecond time-resolved absorption studies have been carried out o
n a cerium porphyrin-phthalocyanine sandwich mixed dimer in the liquid
and solid states. Following excitation, two relaxation processes havi
ng time constants of almost-equal-to 1 and almost-equal-to 40 ps are o
bserved irrespective to the nature of the environment. The first proce
ss is attributed to the relaxation of the excited state of the dimer t
o a low-lying charge transfer state. The second one, much slower, acco
unts for the relaxation of the charge transfer state back to the groun
d state. The comparison of the liquid and solid phase data clearly all
ows the role of the solvent in the relaxation processes to be eliminat
ed.