Fluorescence lifetime measurement of dibenzofuran and monochlorodibenzofuran

Abstract

The fluorescence lifetime of dibenzofuran and monochlorodibenzofuran was measured directly using a picosecond distributedfeedback dye laser and a fast-response microchannel-plate photomultiplier. The fluorescence lifetimes for dibenzofuran and monochlorodibenzofuran were determined to be 10.870.5 ns and ca. 1 ns, respectively, suggesting that the fluorescence quantum yield is reduced 10-fold by intersystem crossing induced by a chlorine atom in a dibenzofuran molecule. These findings highlight the advantages of a picosecond laser for the efficient multiphoton ionization of polychlorinated dibenzofurans.

First quantitative measurements by IR spectroscopy of dioxins and furans by means of broadly tunable quantum cascade lasers

“…Gas phase absorption spectroscopy and laser induced fluorescence [5,6] have been used for analysis in the UV spectral region. Moreover dioxin measurements have been performed by means of both fluorescence lifetime [7] and plasmonic-resonance [8] techniques. In order to detect dioxins and furans in the infrared (IR) region, techniques such as Raman spectroscopy [9] and, above all, gas chromatography/matrix isolation/Fourier transform (FT) spectroscopy [10] have been employed.…”