Spectroscopic Characterization of the Reaction Products between the Criegee Intermediate CH2OO and HCl

Pulsed Fourier‐transform microwave experiments have been performed to probe the products resulting from the reaction between HCl and the simplest Criegee intermediate, CH2OO, where the reaction is considered to be important in atmospheric chemistry. The experimentally determined rotational parameters interpreted with the help of quantum chemical calculations support the identification of chloro‐methyl hydroperoxide molecule as the primary product of this reaction. The reaction system containing CH2OO and HCl is studied by pure rotational spectroscopy. CH2OO molecules are generated in the discharged plasma of a CH2I2/O2 mixture, which contains a small amount of HCl enough to react with CH2OO. The observed species is identified as the most stable conformer of chloro‐methyl hydroperoxide.