A non-mass-dependent oxygen isotope effect in the production of ozone from molecular oxygen: The role of molecular symmetry in isotope chemistry

Abstract

It was previously reported that the reaction products from the synthesis of ozone in an electric discharge through molecular oxygen display a non‐mass‐dependent (NoMaDic) oxygen isotope effect. In this paper, we report a detailed characterization of the isotope effect, including the effect of molecular oxygen pressure, and the presence of a chemically inert third body (helium). The NoMaDic effect is due to an isotopically selective stabilization of the O₃ formation reaction intermediate, possibly resulting from the ability of the different isotopomers to exhibit different molecular symmetries.