Basic features of Ne*-HX (X = Cl, Br) chemi-ionization reactions

Area of Science:

• Chemical Physics
• Atomic and Molecular Collisions
• Reaction Dynamics

Background:

• Chemi-ionization reactions involving excited Ne*(3P2,0) atoms provide insights into fundamental collision processes.
• Understanding the stereodynamics of these reactions is crucial for controlling chemical outcomes.

Purpose of the Study:

• To comparatively analyze total and partial ionization cross sections for Ne*(3P2,0)-HX (X = Cl, Br) collisions.
• To investigate the similarities and differences in collisional stereodynamics between Ne*-HCl and Ne*-HBr systems.
• To elucidate the role of interaction potentials in selectively opening reaction channels.

Main Methods:

• Experimental measurement of mass spectrometric data for Ne*-HBr chemi-ionization.
• Comparative analysis of new Ne*-HBr data with existing Ne*-HCl data.
• Theoretical consideration of interaction potentials governing reactive collisions.

Main Results:

• Presentation of total and partial ionization cross sections as a function of collision energy (0.02-0.5 eV).
• Identification of similarities and differences in the collisional stereodynamics of Ne*-HCl and Ne*-HBr.
• Observation that reaction channels for parent HX+ ions, associated NeHX+ ions, and NeH+ proton transfer species are selectively opened.

Conclusions:

• The stereodynamics of Ne*-HX collisions are influenced by the specific halogen atom (Cl or Br).
• Interaction potentials play a key role in directing the outcome of reactive collisions.
• Specific orientation and acceptance angles of angular cones determine the selective opening of different reaction pathways.