Absolute Dissociative Electron Attachment Cross Sections in Acetylene and its Deuterated Analogue

Olivier May; Juraj Fedor; Michael Allan

doi:10.2533/chimia.2010.173

Absolute Dissociative Electron Attachment Cross Sections in Acetylene and its Deuterated Analogue

Authors

Olivier May Department of Chemistry, University of Fribourg, Ch. du Musée 9
Juraj Fedor
Michael Allan

DOI:

https://doi.org/10.2533/chimia.2010.173

Keywords:

Absolute cross section, Dissociative electron attachment, Isotope effect

Abstract

An instrument for the measurement of absolute dissociative electron attachment cross sections was constructed and applied to two prototype molecules, acetylene (C2H2) and deuterated acetylene (C2D2). The isotope effect at the first dissociative electron attachment band at 3 eV was determined–the cross section for C2D?/C2D2 is 14.4 times smaller than that for C2H?/C2H2. The results play a central role in validating recent theoretical work of Chourou and Orel. The dominant fragments at the second dissociative attachment band around 8 eV are the light fragments H? or D?. These bands exhibit weaker isotope effects.