Supporting data for: Observations of gas-phase products from the nitrate radical-initiated oxidation of four monoterpenes

Chemical ionization mass spectrometry with the nitrate reagent ion (NO- 3 CIMS) was used to investigate the products of the nitrate radical (NO3) initiated oxidation of four monoterpenes in laboratory chamber experiments. a-Pinene, b-pinene, d-3-carene, and a-thujene were studied. The major gas-phase species produced in each system were distinctly different, showing the effect of monoterpene structure on the oxidation mechanism and further elucidating the contributions of these species to particle formation and growth. By comparing groupings of products based on the ratios of elements in the general formula CwHxNyOz, the relative importance of specific mechanistic pathways (fragmentation, termination, and radical rearrangement) can be assessed for each system. Additionally, the measured time series of the highly oxidized reaction products provideinsights into the ratio of relative production and loss rates of the high-molecular-weight products of the d-3-carene system. The measured effe...