The in situ formation of large molecules in dense interstellar clouds
E. Herbst;
ApJ, 1991, 366, 133

ABSTRACT:A simple model has been developed to estimate the abundances of large hydrocarbon molecules produced by gas-phase, ion-molecule reactions in dense interstellar clouds. Hydrocarbons through 30 carbon atoms in size are considered in the model. Molecular complexity is built up via synthetic reactions involving smaller hydrocarbon neutral and ions. A quasi-time-dependent model has been utilized in which the abundances of hydrocarbons with fewer than 10 carbon atoms are fixed at values calculated in a previous model. The time dependence of the abundances of the more complex hydrocarbons is then followed. The results show that, with favorable values for important rate coefficients, it is possible to produce sizeable abundances of hydrocarbon molecules exceeding about 20 carbon atoms in size an in a time scale of not greater than 10 to the 6th yr.
KEYWORDS: astronomical models, interstellar chemistry, interstellar matter, molecular clouds, abundance, computational astrophysics, hydrocarbons
CODE: herbst91