Details

Autor(en) / Beteiligte

• Feldman, Vladimir I.
• Ryazantsev, Sergey V.
• Saenko, Elizaveta V.
• Kameneva, Svetlana V.
• Shiryaeva, Ekaterina S.

Titel

Matrix isolation model studies on the radiation-induced transformations of small molecules of astrochemical and atmospheric interest

Ist Teil von

• Radiation physics and chemistry (Oxford, England : 1993), 2016-07, Vol.124, p.7-13

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The radiation-induced transformations of small molecules at low temperatures play an important role in the interstellar, planetary and atmospheric chemistry. This work presents a review of our recent model studies on the radiation chemistry of relevant molecules in solid noble gas (Ng) matrices, including some preliminary new results. Among the triatomic molecules, water and carbon dioxide were studied in detail. The radiation-induced degradation of isolated H2O yields hydrogen atoms and OH radicals, while oxygen atoms are produced at higher doses. Isolated CO2 molecules are decomposed to yield CO and trapped oxygen atoms. Upon annealing the trapped O and H atoms are mobilized selectively at different temperatures and react with other trapped species. The formation of HCO and HOCO radicals was observed in the mixed H2O/CO2/Ng systems. Other studies were concerned with the radiation-induced degradation of simple organic molecules (methanol, formic acid) and chlorofluorocarbons (CFCl3, CF2Cl2). Preliminary results for methanol revealed deep dehydrogenation yielding HCO and CO, whereas CO2, CO and HOCO were detected as primary products for formic acid. In the case of chlorofluorocarbons, significance of ionic channels was demonstrated. The implications of the results for modeling the processes in astrochemical ices and atmosphere are discussed. •Matrix isolation was used to simulate the radiation-induced transformations in ices.•Recent results on the radilolysis of astrochemically relevant molecules are reviewed.•Reactions of thermally mobilized O and H atoms in solid noble gases are discussed.•Comparison between photolysis and radiolysis in matrices is presented.•The role of weak intermolecular interactions in the ice radiolysis is demonstrated.