Reactive Collisions at Cold Temperatures of Interstellar Cloulds

Abstract

A complex chemistry takes places in cold molecular clouds in the interstellar medium. Many organic molecules presents a barrier in gas phase and for this reason their reactions are typically modelled at surfaces of ices. However, recently it has been found a non-Arrhenius behavior at low temperatures (below 100K) with a fast increase of the rate with decreasing temperature~\cite{Shannon-etal:13,Gomez-Martin-etal:14,Antinolo-etal:16} for the methanol reaction with OH. The reaction of formaldehide with Oh also shows this behavior~\cite{Ocana-etal:17}, and the non-Arrhenius behavior at low temperature is simulated by Quassi-classical simulations on a full-dimension potential energy surface developed for this purpose.