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Multiple ionization and hydrogen loss from neutral and positively-charged coronene
Chiara Paris1, Manuel Alcamí1, Fernando Martín1
1Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
The Journal of Chemical Physics
|June 2, 2014
Summary
Positively-charged coronene (C24H12(q+)) exhibits remarkable stability due to efficient charge delocalization. Its fragmentation pathways, including hydrogen and H2 loss, vary significantly with increasing positive charge.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- Coronene (C24H12) is a polycyclic aromatic hydrocarbon with unique electronic properties.
- Understanding the stability and fragmentation of its charged species is crucial for potential applications.
Purpose of the Study:
- Investigate the structure and stability of neutral and positively-charged coronene (C24H12(q+)).
- Determine ionization potentials, infrared spectra, and dissociation pathways.
- Analyze fragmentation barriers and potential energy surfaces for hydrogen loss channels.
Main Methods:
- Density Functional Theory (DFT) calculations were employed.
- Adiabatic and vertical ionization potentials were computed up to q = 9.
- Infrared spectra, dissociation energies, and potential energy surfaces were analyzed.
Main Results:
- Positively-charged coronene demonstrates exceptional stability owing to extensive charge redistribution.
- Computed dissociation energies reveal competition among various hydrogen loss channels.
- The dominant fragmentation channel is charge-dependent, involving H2, H2(+), or H(+) loss.
Conclusions:
- The high stability of charged coronene is confirmed.
- Fragmentation mechanisms are intricately linked to the molecule's charge state.
- Specific loss channels (H2, H2(+), H(+)+H(+)) are identified as dominant at different charge levels.
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