Picosecond Transient Absorption of Xanthene Dyes*
نویسندگان
چکیده
After oneand two-colour ps-excitation the transient absorption of rose bengal, erythrosin B and eosin Y in the spectral range from 450 to 670 nm was probed using picosecond continuum pulses generated in H2O—D 2 O mixture. Our experiments showed for all dyes a high T1—Tn absorption signal above 590 nm where no ground state absorption occurs. These excited triplet states can be effectively populated by a delayed second pump pulse. Their properties with special attention to reverse intersystem crossing processes from Tn to Sx are discussed.
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