Low pressure chemiluminescent reaction of molecular fluorine with dimethyl sulfoxide and the effects of added oxygen

Abstract

The spectra from the chemiluminescent reaction of dimethyl sulfoxide (DMSO) with molecular fluorine have been studied at pressures below 1 Torr. The spectra were examined for changes occurring upon variation of the reactant partial pressures, substitution of deuterated DMSO and the coaddition of molecular oxygen. In the wavelength region 4500–8800 Å, the spectra are dominated by emission from HCF (Ã) or DCF (Ã) at high F 2 concentrations or by emission from CH 2S (ã) or CD 2S (ã) at low F 2 concentrations. Emission from vibrationally excited HF is observed in the hydrogen system but DF is not observed in the deuterium system. Fluorescence and phosphorescence from SO 2 are observed between 2700 and 4500 Å. A weak set of emission bands near 2600 Å is tentatively assigned to SO(A). The addition of O 2 leads to the production of intense emission from OH(A) or OD(A) in the reactions of DMSO-h 6 or DMSO-d 6 respectively. The addition of O 2 to the DMSO-d 6—F 2 system leads to the production of intense chemiluminescence from CD 2O, while CH 2O was totally absent in the analogous reaction of the hydrogen-containing compound. Mechanisms for the formation of the emitters are proposed based on this and previous work.