Figure 2.

Condensed reaction mechanism for isoprene and β-pinene oxidation via NO₃ (adapted from Schwantes et al., 2015 and Boyd et al., 2015). For brevity, only products generated from the dominant peroxy radicals (RO₂) are shown. R′ represents an alkoxy radical, carbonyl compound, or hydroxy compound. Two of the largest uncertainties in β-pinene oxidation are shown in red: (1) quantification of product yields from the RO₂+ HO₂ channel and (2) identification of carbonyl products formed from RO₂ reaction with NO₃, RO₂, or HO₂ (see text for more details).