The measurements of picosecond fluorescence lifetimes with high accuracy and subpicosecond precision

Systematic studies of the fluorescence picosecond lifetimes determination b y laser-excited time-correlated single-photon-counting (TCSPC) have been un dertaken. The results have been used to develop methods for determining lif etimes with much smaller error and much greater reproducibility than any hi therto reported. The error in the determination of the lifetimes ( three st andard deviations) can be as low as that in simulations and amounts to 0.01 FWHM of the IRF. The lifetimes determined for the second excited singlet s tate of xanthione in toluene (5.1 +/-0.3 ps) and in benzene (8.1 +/-0.3 ps) can be treated as reliable standards of picosecond lifetimes. (C) 2001 Els evier Science BN. All rights reserved.