The Effects of Molecular Anions on the Chemistry of Dark Clouds

Abstract

We have investigated the role of molecular anion chemistry in pseudo-time dependent chemical models of dark clouds. With oxygen-rich elemental abundances, the addition of anions results in a slight improvement in the overall agreement between model results and observations of molecular abundances in TMC-1 (CP). More importantly, with the inclusion of anions, we see an enhanced production efficiency of unsaturated carbon-chain neutral molecules, especially in the longer members of the families CnH, CnH2, and HCnN. The use of carbon-rich elemental abundances in models of TMC-1 (CP) with anion chemistry worsens the agreement with observations obtained in the absence of anions.

Accepted for publication in ApJ, 24 pages, 5 figures

References in corpus (5)

• Polycylcic Aromatic Hydrocarbons (PAH's) in dense cloud chemistry
• Detection of C5N- and vibrationally excited C6H in IRC +10216
• The effect of uncertainties on chemical models of dark clouds
• Search for anions in molecular sources: C4H- detection in L1527
• Hydrocarbon anions in interstellar clouds and circumstellar envelopes

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