Absolute cross sections for O−, SO−, and C− formation from OCS

Determine the absolute cross sections for the formation of O−, SO−, and C− anions in collisions of 0–45 eV electrons with carbonyl sulfide (OCS), which were not obtained in this study due to low count rates that prevented absolute cross-section measurements for these non-S− channels.

Background

This paper reports absolute dissociative electron attachment (DEA) cross sections for S− from OCS using the relative flow technique, and identifies additional anionic fragments (O−, SO−, and C−) at higher energies where ion-pair dissociation becomes important. However, low count rates precluded determination of absolute cross sections for the non-S− channels.

Absolute cross sections for these channels are important for modeling electron-driven chemistry in atmospheres and plasmas, but the present measurements provided only relative information (and, in the case of C−, even the ion-yield curve was not obtained). Establishing these absolute cross sections across the 0–45 eV energy range would complete the quantitative picture of anion formation in electron–OCS collisions.