Abstract
We employed density functional theory (DFT) calculations to model the photoionization behavior of benzene and small polycyclic aromatic hydrocarbons when they are embedded in a matrix of water ice in order to investigate issues raised by recent experimental work by Gudipati and Allamandola. The ionization energies of benzene, naphthalene, anthracene, and pyrene were found to be lowered by 1.5-2.1 eV in water ice. Low-lying vertical electronic excitation energies were computed with time-dependent DFT for both neutral and ionized species and are found in both cases to be remarkably unaffected by the ice matrix. Chemical behavior in ultraviolet-photoprocessed ices is also discussed, with a focus on electron recombination and pathways leading to phenol and analogous products.
Original language | English (US) |
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Pages (from-to) | 342-345 |
Number of pages | 4 |
Journal | Astrophysical Journal |
Volume | 607 |
Issue number | 1 I |
DOIs | |
State | Published - May 20 2004 |
Externally published | Yes |
Keywords
- Astrochemistry
- ISM: molecules
- Molecular processes
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science