Knowledge Bank

Alkylthio radicals $(RS,R=CH3,C2H5$, andi-$C3H7$) are involved in the chemistry of sulfur-rich fuels. These radicals were produced by excimer laser photolysis of therecursor dialkyl disulphide $(R2S2)$. The photolyzed fragments were then probed by a frequency doubled Nd: YAG-pumped dye laser and therotationally-resolved excitation spectra of these radicals were recordedin the UV. Optogalvanic transitions of Ne and Ar were used to calibratethe wavelength o the recorded excitation spectra. Rotational analysis of several bands of the electronic system of three alkylthioradicals was carried out. Precise rotational parameters for both the upper and lower electronic states involved in the transitions were obtained for the three radicals.