Experimental and Theoretical Study on the Ethane and Acetylene Formation from Electron Irradiation of Methane Ices

Marianna Barberio, Roberta Vasta, Pasquale Barone, Giulio Manicò, Fang Xu

Astronomy and Physics Department, University of Catania, Catania, Italy.
Physics Department of Calabria Univeristy, Rende, Italy.
Physics Department of Calabria Univeristy, Rende, Italy; National Research Council-CNR, Magna Graecia University, Catanzaro, Italy.

DOI: 10.4236/wjcmp.2013.31003                

Abstract

In this work we present an experimental and theoretical study on the formation of ethane and acetylene from solid methane condensed at 20 K and irradiated with a 500 - 3000 eV electron beam. The experiments were monitored with Thermal Desorption Spectroscopy. We observe that the electron irradiation induced a dehydrogenation of methane and a consequent formation of CH_x (x = 1, 2, 3) fragments. Furthermore, in the solid during irradiation, a simple recombinetion reaction in the solid between two adjacent CH_x molecules may form HC≡CH, H₂C=CH₂, and H₃C-CH₃ with a triple, double, and single carbon-carbon bond, respectively. The formed amount of ethane and acetylene increases with irradiation time and reaches a saturation value.

 

Keywords

Solid Ices; Ethane Formation; Acetylene Formation; Electron Irradiation

Conflicts of Interest

The authors declare no conflicts of interest.

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