Conformational analysis of simple oxygenated hydrocarbons in a solid parahydrogen matrix

Abstract

Acetone, acetaldehyde, propylene oxide, propionaldehyde, and 2-propanol are all simple oxygen-containing organic molecules, and play an important role in combustion chemistry, atmospheric chemistry, and astrochemistry. These small molecules are often produced by chemical reactions or UV photolysis of larger molecules containing oxygen atoms. Thus, knowing the IR spectrum of these molecules is important for the identification of (photo)chemical processes of various molecules. In this study, the IR spectra of these five common organic molecules were studied using parahydrogen (pH2) matrix isolation with Fourier transform infrared spectroscopy. Conformational analysis of the IR spectra revealed two conformers of propionaldehyde and 2-propanol exist in the pH2 matrix at 3.8 K. This work will be useful for the identification of products in future pH2 photochemistry experiments.