Molecular mechanism for rapid autoxidation in α-pinene ozonolysis

• DOI: 10.1038/s41467-021-21172-w
• Publication Date: 2021-02-09T21:23:32Z
• Authors: Siddharth Iyer; Matti P. Rissanen; Rashid Valiev; Shawon Barua; Jordan E. Krechmer; Joel Thornton; Mikael Ehn; Theo Kurtén
• Keywords: Autoxidation; Pinene

Aerosol affects Earth's climate and the health of its inhabitants. A major contributor to aerosol formation is oxidation volatile organic compounds. Monoterpenes are an important class compounds, recent research demonstrate that they can be converted low-volatility precursors on sub-second timescales following a single oxidant attack. The α-pinene + O3 system particularly efficient in this regard. However, actual mechanism behind conversion not understood. key challenge steric strain created by cyclobutyl ring products. This hinders subsequent unimolecular hydrogen-shift reactions essential for lowering volatility. Using quantum chemical calculations targeted experiments, we show excess energy from initial ozonolysis reaction lead novel intermediates without strain, allowing rapid products with up 8 oxygen atoms. likely route atmospheric formation.