Enhancement of Atmospheric Nucleation by Highly Oxygenated Organic Molecules: A Density Functional Theory Study
Enhancement of Atmospheric Nucleation by Highly Oxygenated Organic Molecules: A Density Functional Theory Study
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高含氧有机分子增强大气成核：密度泛函理论研究
DOI：
10.1021/acs.jpca.9b03142
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发表时间：
2019
影响因子：
2.9
通讯作者：
Huang Wei
中科院分区：
文献类型：
--
作者：
Zhao Feng;Feng Ya-Juan;Liu Yi-Rong;Jiang Shuai;Huang Teng;Wang Zi-Hang;Xu Cai-Xin;Huang Wei
气粒转化形成的新粒子（NPF）是大气气溶胶的主要来源。高氧有机分子（HOMs）和硫酸（SA）是NPF的重要参与者。2-甲基甘油（MGA）是异戊二烯衍生的二次有机气溶胶的示踪剂，是HOMs的一种。采用密度泛函理论和大气簇动力学模拟研究了MGA与SA的成核机理，并与MGA与甲磺酸（MSA）的成核机理进行了比较。我们的理论研究表明，（MGA）（SA）和（MGA）（MSA）集群分别是（MGA）i(SA)j（i= 1-2,j= 1-2）和（MGA）i(MSA)j（i= 1-2,j= 1-2）中最稳定的集群。（MGA）（SA）和（MGA）（MSA）团簇的形成速率都很大，可能对NPF有重要贡献。结果表明，MGA在大气中不太可能发生同分子成核，MGA和SA主要以异源二聚体的形式有效促进异分子成核。MSA在与MGA形成团簇方面表现出与SA相似的性质，但比SA稍弱。
New particle formation (NPF) by gas–particle conversion is the main source of atmospheric aerosols. Highly oxygenated organic molecules (HOMs) and sulfuric acid (SA) are important NPF participants. 2-Methylglyceric acid (MGA), a kind of HOMs, is a tracer of isoprene-derived secondary organic aerosols. The nucleation mechanisms of MGA with SA were studied using density functional theory and atmospheric cluster dynamics simulation in this study, along with that of MGA with methanesulfonic acid (MSA) as a comparison. Our theoretical works indicate that the (MGA)(SA) and (MGA)(MSA) clusters are the most stable ones in the (MGA)i(SA)j(i= 1–2,j= 1–2) and (MGA)i(MSA)j(i= 1–2,j= 1–2) clusters, respectively. Both the formation rates of (MGA)(SA) and (MGA)(MSA) clusters are quite large and could have significant contributions to NPF. The results imply that the homomolecular nucleation of MGA is unlikely to occur in the atmosphere, and MGA and SA can effectively contribute to heteromolecular nucleation mainly in the form of heterodimers. MSA exhibits properties similar to SA in its ability to form clusters with MGA but is slightly weaker than SA.