Triplet state characteristics of IR laser dyes: A pulse radiolysis study
نویسندگان
چکیده
The IR-dyes, having the absorption maximum in the range of 600 nm to 1100 nm, are expected to have very low triplet e nergy level. The triplet-triplet (T-T) absorption spectra and decay characteris tics have becn invcstigated for four IR laser dyes, namely, IR-140, IR-144, Q-Switch I and Q-Switch 5. Triplet state of these IR dyes are generated by electron pulse radiolysis in benzene-benzonitrile (BZ-BZN 80:20, % v/v) solvent mixture. Energy transfer from the pulse radiolytically generated anthracene triplet confirms the formation of triplet state of these IR dyes. Triplet state charac terist ics o f these IR dyes have been measured. Using various triplet donors and acceptors, the triplct energy level s of these dyes have been estimated.
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