Interactive comment on “Formation of highly oxidized multifunctional compounds: autoxidation of peroxy radicals formed in the ozonolysis of alkenes

Hydroxy nitrate production in the OH-initiated oxidation of alkenes

Alkenes are oxidized rapidly in the atmosphere by addition of OH and subsequently O2 leading to the formation of β-hydroxy peroxy radicals. These peroxy radicals react with NO to form β-hydroxy nitrates with a branching ratio α. We quantify α for C2–C8 alkenes at 295 K± 3 and 993 hPa. The branching ratio can be expressed as α = (0.045± 0.016)×N−(0.11± 0.05)whereN is the number of heavy atoms (e...

Interactive comment on “Understanding the formation of biogenic secondary organic aerosol from α-pinene in smog chamber studies: role of organic peroxy radicals” by B. Bonn et al

This paper presents a hypothesis on how new particles may be formed from organic precursors in the absence of sulphuric acid. The authors propose a secondary ozonide, which is the product of a stabilized Criegee intermediate and a carbonyl compound, to be the nucleating agent, and peroxy radicals to be responsible for the initial growth. At a later stage “regular” condensation is assumed to tak...

Supplement of Different pathways of the formation of highly oxidized multifunctional organic compounds (HOMs) from the gas-phase ozonolysis of β-caryophyllene

Computational Model of Reaction Mechanism of Alkyl Peroxy Radicals with Organic Compounds in the Presence and Absence of Oxygen

On the basis of experimental data a kinetic model for the heterogeneous interaction between alkylperoxyradicals and organic compounds in Langmuir- Hinshelwood approach at room temperature has been offered.The effect of oxygen on the kinetics of process in the presence, [O2]o = 1 x 1011 – 1.6 x 1012 molecules.cm-2, and absence of oxygen has been analyzed. Over time the chain degenerate branching...

Hydroxyl radical-induced formation of highly oxidized organic compounds

Explaining the formation of secondary organic aerosol is an intriguing question in atmospheric sciences because of its importance for Earth's radiation budget and the associated effects on health and ecosystems. A breakthrough was recently achieved in the understanding of secondary organic aerosol formation from ozone reactions of biogenic emissions by the rapid formation of highly oxidized mul...