Photochemistry of a 1 : 1 hydrogen-bonded CH3CN : HCOOH complex under astrochemically-relevant conditions

Abstract

The interstellar medium is characterized by a complex chemistry, especially on the surface of ice grains in molecular clouds. In an attempt to investigate possible reactions leading to exobiologically-relevant species, laboratory experiments dealing with the formation of nitrogen- and oxygen-bearing organic molecules from precursors that are present in the solid phase, on the surface of ice grains, are of primary importance. The aim of the present work was to investigate the formation of a non-covalent complex between CH₃CN and HCOOH. For that purpose, FT-IR spectroscopy was used in combination with the rare-gas matrix technique. The experimental spectra were compared with the theoretical ones obtained with the help of quantum-chemical calculations. This combination between a theoretical and an experimental approach allowed us to propose a structure for the hydrogen-bonded complexes experimentally observed.