Electron Bombardment of Amorphous Thione Ices—Thioacetamide as a Case Study

Sándor Góbi; Barbara Keresztes; Tarczay György

Abstract

Amorphous thioacetamide (TA) ice was deposited at 10 K and was bombarded with 5 keV electrons. TA ices were shown to decompose into acetonitrile (ACN, H3C–C≡N), cyanide anion ([CN]–), and ketenimine (H2C=C=NH). The experiments were repeated with TA ices mixed with H2O, to assess the effect of an oxygen source. In this case, the formation of cyanate anion ([OCN]–) was also observed besides those seen in the pure TA ice experiment. This study is the first that aims to reveal the decomposi􀆟on pathways of a thioamide upon energetic irradiation in the low-temperature ice phase.

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