duley96

The formation of H$_2$ by H-atom reaction with grain surfaces
W. W. Duley;
MNRAS, 1996, 279, 591

ABSTRACT:A model for H_2 formation by reaction of H-atoms with the surface of carbonaceous grains is developed. Such reactions, which involve interstitial H-atoms at low grain temperature and H-atoms bonded to -CH, -CH_2 and -CH_3 groups at higher temperature, occur promptly on the collision of an H-atom with a grain surface. The rate of hydrogen formation and the efficiency of reaction depend on both gas kinetic and dust temperature. The rate coefficient R (cm^3 s^-1) for H_2 formation using this prompt-reaction model (PRM) can be calculated from laboratory data and is consistent with measured values of R. The dependence of R on ambient conditions in interstellar clouds can be easily estimated from this prompt-reaction model. R is found to be strongly dependent on gas kinetic temperature T_k and can exceed 10^-17 cm^3 s^-1, even for warm dust, when T_k>~300 K.
KEYWORDS: molecular processes, ism: abundances, dust, extinction, ism: molecules
CODE: duley96

The formation of H$_2$ by H-atom reaction with grain surfaces W. W. Duley; MNRAS, 1996, 279, 591

The formation of H$_2$ by H-atom reaction with grain surfaces
W. W. Duley;
MNRAS, 1996, 279, 591