title: Spectroscopic signatures of ozone at the air-water interface and photochemistry implications.
abstract: First-principles simulations suggest that additional OH formation in the troposphere can result from ozone interactions with the surface of cloud droplets. Ozone exhibits an affinity for the air-water interface, which modifies its UV and visible light spectroscopic signatures and photolytic rate constant in the troposphere. Ozone cross sections on the red side of the Hartley band (290- to 350-nm region) and in the Chappuis band (450-700 nm) are increased due to electronic ozone-water interactions. This effect, combined with the potential contribution of the O3 + hν → O((3)P) + O2(X(3)Σg(-)) photolytic channel at the interface, leads to an enhancement of the OH radical formation rate by four orders of magnitude. This finding suggests that clouds can influence the overall oxidizing capacity of the troposphere on a global scale by stimulating the production of OH radicals through ozone photolysis by UV and visible light at the air-water interface.
authors: Departament de Química Biològica i Modelització Molecular (Institut de Química Avançada de Catalunya-Consejo Superior de Investigaciones Cientificas), E-08034 Barcelona, Spain; anglada@iqac.csic.es Marilia.Martins-Costa@univ-lorraine.fr Manuel.Ruiz@univ-lorraine.fr francisc@purdue.edu.
authors: Josep M
authors: JM
authors: Anglada
authors: Laboratoire Structure et Réactivité des Systèmes Moléculaires Complexes, University of Lorraine, 54506 Vandoeuvre-lès-Nancy, France;Centre National de la Recherche Scientifique (Joint Research Unit 7565), 54506 Vandoeuvre-lès-Nancy, France; and anglada@iqac.csic.es Marilia.Martins-Costa@univ-lorraine.fr Manuel.Ruiz@univ-lorraine.fr francisc@purdue.edu.
authors: Marilia
authors: M
authors: Martins-Costa
authors: Laboratoire Structure et Réactivité des Systèmes Moléculaires Complexes, University of Lorraine, 54506 Vandoeuvre-lès-Nancy, France;Centre National de la Recherche Scientifique (Joint Research Unit 7565), 54506 Vandoeuvre-lès-Nancy, France; and anglada@iqac.csic.es Marilia.Martins-Costa@univ-lorraine.fr Manuel.Ruiz@univ-lorraine.fr francisc@purdue.edu.
authors: Manuel F
authors: MF
authors: Ruiz-López
authors: Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084 anglada@iqac.csic.es Marilia.Martins-Costa@univ-lorraine.fr Manuel.Ruiz@univ-lorraine.fr francisc@purdue.edu.
authors: Joseph S
authors: JS
authors: Francisco
mesh_terms: D001272:Atmosphere / Q000737:chemistry*; D005740:Gases / Q000737:chemistry / Q000528:radiation effects; D017665:Hydroxyl Radical / Q000737:chemistry / Q000528:radiation effects; D010126:Ozone / Q000737:chemistry* / Q000528:radiation effects*; D055668:Photochemical Processes; D010782:Photolysis; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry
chemical_list: D005740:Gases; D014867:Water; D017665:Hydroxyl Radical; D010126:Ozone
keywords: atmospheric chemistry; computer simulations; heterogeneous processes; reactive oxidant species