title: Optical properties of secondary organic aerosols derived from long-chain alkanes under various NOxand seed conditions.
abstract: Long-chain alkanes are a type of important intermediate-volatile organic compounds (IVOCs) in the atmosphere, which contribute to a large proportion of secondary organic aerosol (SOA). However, the optical properties of SOA derived from long-chain alkanes remain poorly understood. Here, we investigate the refractive index (RI) of SOA derived from photo-oxidation of dodecane (C12), pentadecane (C15) and heptadecane (C17) under low-NOxand high-NOxconditions with the absence or presence of inorganic aerosol seeds. The RIs of these SOAs are found to be in the range of 1.33 to 1.57 at the wavelength of 532nm. The results from mass spectroscopy indicate that both reaction mechanisms influenced by NOxlevel and gas-particle partitioning influenced by seeds have important impact on the chemical compositions of SOAs, which further influence the optical properties like RI. Finally, by comparing the RI values to other literature and model results, we suggest that various RIs of SOAs derived from long-chain alkanes should be applied in atmospheric and climate models.
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Junling
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Kun
authors.initials: K
authors.lastname: Li
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China. Electronic address: wangwg@iccas.ac.cn.
authors.forename: Weigang
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Chao
authors.initials: C
authors.lastname: Peng
authors.affiliation: State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China. Electronic address: gemaofa@iccas.ac.cn.
authors.forename: Maofa
authors.initials: M
authors.lastname: Ge
keywords: IVOCs; RIs; SOA