Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-12-23
Astronomy and Astrophysics
Astrophysics
71 pages and 17 figures, consisting of paper (54 pages and 11 figures) and supporting material (17 pages and 6 figures). To be
Scientific paper
10.1063/1.2162901
We present results of classical dynamics calculations, performed to study the photodissociation of water in crystalline and amorphous ice surfaces at a surface temperature of 10 K. Dissociation in the top six monolayers is considered. Desorption of H2O has a low probability (less than 0.5% yield per absorbed photon) for both types of ice. The final outcome strongly depends on the original position of the photodissociated molecule. For molecules in the first bilayer of crystalline ice and the corresponding layers in amorphous ice, desorption of H atoms dominates. In the second bilayer H atom desorption, trapping of the H and OH fragments in the ice, and recombination of H and OH are of roughly equal importance. Deeper into the ice H atom desorption becomes less important and trapping and recombination dominate. The distribution of distances traveled by H atoms in the ice peaks at 6 - 7 Angstroms with a tail going to about 60 Angstroms for both types of ice. The mobility of OH radicals is low within the ice with most probable distances traveled of 2 and 1 Angstroms for crystalline and amorphous ice, respectively. OH is however quite mobile on top of the surface, where it has been found to travel more than 80 Angstroms. Simulated absorption spectra of crystalline ice, amorphous ice, and liquid water are found to be in very good agreement with experiments.
Al-Halabi Ayman
Andersson Stefan
Kroes Geert-Jan
van Dishoeck Ewine F.
No associations
LandOfFree
Molecular dynamics study of photodissociation of water in crystalline and amorphous ice does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Molecular dynamics study of photodissociation of water in crystalline and amorphous ice, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Molecular dynamics study of photodissociation of water in crystalline and amorphous ice will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-696596