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Updated: Jul 23, 2025
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Resonant Fragmentation of the Water Cation by Electron Impact: a Wave-Packet Study
Ignacio Benito-Gómez1, Luis Méndez1, Jaime Suárez1
1Laboratorio Asociado al CIEMAT de Física Atómica y Molecular en Plasmas de Fusión, Departamento de Química, módulo 13, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
Summary
Dissociative recombination (DR) is the primary dissociation pathway for a resonant state in low-energy electron scattering from H₂O⁺. Dissociative excitation (DE) was found to be negligible in this study.
Area of Science:
- Chemical Physics
- Atomic and Molecular Physics
- Quantum Chemistry
Background:
- Low-energy electron scattering experiments probe fundamental molecular interactions.
- Resonant states play a crucial role in electron-molecule collision dynamics.
- Understanding dissociation pathways is key to predicting molecular ion behavior.
Purpose of the Study:
- Investigate the dissociation mechanisms of a specific resonant state in electron-H₂O⁺ scattering.
- Quantify the probabilities of dissociative recombination (DR) and dissociative excitation (DE).
- Analyze the time-evolution of wave packets on potential energy surfaces.
Main Methods:
- Time-evolution wave packet calculations.
- Analysis of potential energy surfaces for resonant and cationic states.
- Focus on the second triplet resonance above the ground state of H₂O⁺.
Main Results:
- Dissociative recombination (DR) was found to be the dominant dissociation pathway, with a probability of approximately 38%.
- Dissociative excitation (DE) following autoionization was observed to be negligible.
- The study focused on autoionization producing the H₂O⁺ (X²B₁) state.
Conclusions:
- Dissociative recombination is the primary dissociation channel for the investigated resonant state in electron-H₂O⁺ collisions.
- Dissociative excitation is an insignificant pathway under the studied conditions.
- The findings contribute to a deeper understanding of electron-molecule interactions and ion dissociation dynamics.
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