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arXiv · 0905.0800

The Effects of Molecular Anions on the Chemistry of Dark Clouds

Catherine Walsh·Nanase Harada·Eric Herbst·T. J. Millar
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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.

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Catherine Walsh, Nanase Harada, Eric Herbst, T. J. Millar. 2009-05-06. The Effects of Molecular Anions on the Chemistry of Dark Clouds. https://doi.org/10.1088/0004-637x%2F700%2F1%2F752

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