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Hexachlorobenzene-negative ion formation in electron attachment experiments.
1Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal. plimaovieira@fct.unl.pt.
Physical Chemistry Chemical Physics : PCCP
|May 24, 2022
Summary
This study investigates hexachlorobenzene (C6Cl6) negative ion formation using low-energy electrons. The parent anion is the most stable, but fragmentation yields Cl-, Cl2-, C6Cl4-, and C6Cl5- anions.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Molecular Physics
Background:
- Hexachlorobenzene (C6Cl6) is a persistent organic pollutant.
- Understanding its electron interaction is crucial for environmental and chemical applications.
Purpose of the Study:
- To comprehensively study the formation of hexachlorobenzene negative ions.
- To analyze the fragmentation patterns resulting from low-energy electron attachment.
Main Methods:
- Gas-phase crossed beam experiment to probe electron interactions from 0 to 12 eV.
- Quantum chemical calculations to determine electronic structure and thermochemistry.
Main Results:
- The most intense ion observed was the non-dissociated parent hexachlorobenzene anion.
- Fragment anions identified include Cl-, Cl2-, C6Cl4-, and C6Cl5-.
- Cl- formation involves π*/σ* coupling and exhibits vibrational excitation signatures.
Conclusions:
- Low-energy electron attachment to hexachlorobenzene leads to complex fragmentation.
- Quantum chemical calculations support experimental findings on ion structures and formation pathways.
- Jahn-Teller distortion may influence chlorine anion yield.
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