Supplementary material to "Key Role of Nitrogen-containing Oxygenated Organic Molecules (OOMs) in SOA Formation Evidenced by OH/NO ₃ -induced Terpinolene Oxidation"

S1 Volatility Estimation and ClassificationThe group contribution method, i.e., SIMPOL.1 from the GECKO-A website (https://geckoa.lisa.u-pec.fr), is utilized to estimate the saturated vapor pressure.However, the dataset involved in SIMPOL.1 is limited in the calculation of the contribution of -OONO2 group, except for peroxyacetyl nitrate (PAN).Therefore, we also employed the optimized molecular formula parameterization method to assess the volatility of the OOMs 1, 2 , which considers the -OOH functional group of OOMs to enhance predictive accuracy.The governing equation is given below - Among them, 0 =0.475, =0.475, 0 =0.2, =0.9, =2.5.The OOMs generated by the further oxidation of alkyl radical (Ter-R) initiated by OH/NO3 radical from terpinolene was classified according to the volatility classification scheme for organic compounds proposed by Donahue et al.( 2012) 3 , i.e., ELVOC ( C * < 310 -4 g m -3 ), LVOC ( 310 -4 < C * < 0.3 g m -3 ), SVOC (0.3 < C * < 300 g m -3 ), intermediate volatility organic compounds (IVOC, 300 < C * < 310 6 g m -3 ) and volatile organic compounds ( VOC, C * > 310 6 g m -3 ), of which, ELVOC and LVOC are basically existed in the particulate phase, and SVOC is distributed in both gas phase and particle phase, depending on the atmospheric conditions.