Determination Of The Oxygen Quenching Rates Of The Dual Fluorescence Of Vapor Phase Fluoranthene

Dual fluorescence of fluoranthene in the gas phase was studied. The oxygen quenching coefficients were determined in the excitation wavelength range between 240 and 360 nm. The dependence of the fluorescence on emission and excitation wavelength was also established. The quenching rates for selected excitation wavelengths were calculated and compared to values reported in the literature. When fluoranthene at 553 K is excited at 310, 340, and 360 nm the quenching rates for the S,->Sotransition are 3.24 xlO* L mol'V, 5.13 xlO* L mol"' s"* and 6.94 xlO^ L mol"' s~* respectively. The oxygen quenching rate for the S2->So transition, observed at 375 nm is greater than 1x10" L mol"* s"'. [1.97x10*° L mol"* s"' when the two bands are not separated]