Electron impact single and double ionization and dissociation: revisiting CF₄ and CHF₃ with an improved experimental...

Area of Science:

• Atomic and Molecular Physics
• Plasma Physics
• Environmental Science

Background:

• Fluorinated molecules like CF4 and CHF3 are potent greenhouse gases.
• Understanding electron interactions with these molecules is vital for atmospheric and industrial applications.
• Previous experimental data on ionization and dissociation cross sections are limited.

Purpose of the Study:

• To measure absolute total and partial ionization cross sections for electron collisions with CF4 and CHF3.
• To investigate dissociation channels and their differences between CF4 and CHF3.
• To provide accurate data for evaluating the environmental impact and industrial applications of these gases.

Main Methods:

• Recoil-ion momentum spectroscopy was employed to measure cross sections.
• Full acceptance for energetic ionic fragments ensured comprehensive data collection.
• The relative-flow technique was used for absolute cross section normalization.

Main Results:

• Absolute cross sections for single and double ionization, as well as dissociation, were determined for electron energies from 20 eV to 1 keV.
• Data were compared with existing experimental results and theoretical models.
• Specific differences in dissociation channels between CF4 and CHF3 were identified and discussed.

Conclusions:

• The study provides crucial cross-section data for electron interactions with CF4 and CHF3.
• These findings aid in assessing the environmental impact of these greenhouse gases.
• The data are valuable for optimizing plasma and industrial processes involving fluorinated compounds.