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Insights into H2 formation in space from ab initio molecular dynamics.

ABSTRACT: Hydrogen formation is a key process for the physics and the chemistry of interstellar clouds. Molecular hydrogen is believed to form on the carbonaceous surface of dust grains, and several mechanisms have been invoked to explain its abundance in different regions of space, from cold interstellar clouds to warm photon-dominated regions. Here, we investigate direct (Eley-Rideal) recombination including lattice dynamics, surface corrugation, and competing H-dimers formation by means of ab initio molecular dynamics. We find that Eley-Rideal reaction dominates at energies relevant for the interstellar medium and alone may explain observations if the possibility of facile sticking at special sites (edges, point defects, etc.) on the surface of the dust grains is taken into account.

SUBMITTER: Casolo S

PROVIDER: S-EPMC3637713 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Insights into H2 formation in space from ab initio molecular dynamics.

Casolo Simone S Tantardini Gian Franco GF Martinazzo Rocco R

Proceedings of the National Academy of Sciences of the United States of America 20130409 17

Hydrogen formation is a key process for the physics and the chemistry of interstellar clouds. Molecular hydrogen is believed to form on the carbonaceous surface of dust grains, and several mechanisms have been invoked to explain its abundance in different regions of space, from cold interstellar clouds to warm photon-dominated regions. Here, we investigate direct (Eley-Rideal) recombination including lattice dynamics, surface corrugation, and competing H-dimers formation by means of ab initio mo ...[more]

PMID: 23572584

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Insights into H2 formation in space from ab initio molecular dynamics.

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Insights into H2 formation in space from ab initio molecular dynamics.

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