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arXiv · 1806.09352

Absolute cross-sections of fragment negative ions in electron collisions with difluoromethane

Dipayan Chakraborty·Dhananjay Nandi
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Abstract

Dissociative electron attachment (DEA) and ion-pair dissociation (IPD) processes of Difluoromethane (CH$_2$F$_2$) have been studied in the incident electron energy range 0 to 45 eV. Three different fragment anions (F$^-$, CHF$^-$ and F$_2^-$) are detected in the DEA range and two anions (F$^-$ and CHF$^-$) are detected in IPD range. Absolute cross-section of the F$^-$ fragment ion is measured for the first time. Three different resonances for both F$^-$ and CHF$^-$ ions and one single resonance peak for the F$_2^-$ ions are observed. Constant increase in ion counts above 8 eV incident electron energy indicates the involvement of IPD process. From the experimental observation, it is speculated that near 11 eV incident electron energy both DEA and IPD processes occur simultaneously.

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Dipayan Chakraborty, Dhananjay Nandi. 2018-06-25. Absolute cross-sections of fragment negative ions in electron collisions with difluoromethane. https://doi.org/10.1103/physreva.102.052801

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