title: Bidirectional Interaction of Alanine with Sulfuric Acid in the Presence of Water and the Atmospheric Implication.
abstract: Amino acids are recognized as important components of atmospheric aerosols, which impact on the Earth's climate directly and indirectly. However, much remains unknown about the initial events of nucleation. In this work, the interaction of alanine [NH2CH(CH3)COOH or Ala], one of the most abundant amino acids in the atmosphere, with sulfuric acid (SA) and water (W) has been investigated at the M06-2X/6-311++G(3df, 3pd) level of theory. We have studied thermodynamics of the hydrated (Ala)(SA) core system with up to four water molecules. We found that Ala, with one amino group and one carboxyl group, can interact with H2SO4 and H2O in two directions and that it has a high cluster stabilizing effect similar to that of ammonia, which is one of the key nucleation precursor. The corresponding Gibbs free energies of the (Ala)(SA)(W)n (n = 0-4) clusters formation at 298.15 K predicted that Ala can contribute to the stabilization of small binary clusters. Our results showed that the hydrate distribution is temperature-dependent and that a higher humidity and temperature can contribute to the formation of hydrated clusters.
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.|University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Chun-Yu
authors.initials: CY
authors.lastname: Wang
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.|University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Chen
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.
authors.forename: Yi-Rong
authors.initials: YR
authors.lastname: Liu
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wen
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.
authors.forename: Ya-Juan
authors.initials: YJ
authors.lastname: Feng
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.|University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hong
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.
authors.forename: Teng
authors.initials: T
authors.lastname: Huang
authors.affiliation: Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences , Hefei, Anhui 230031, China.|School of Environmental Science & Optoelectronic Technology, University of Science and Technology of China , Hefei, Anhui 230026, China.|Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Huang