title: Ab Initio Study on the Mechanism of Tropospheric Reactions of the Nitrate Radical with Alkenes: Ethene.
abstract: A mechanism for the reaction of the NO(3) radical with the simplest alkene, ethene, is proposed. The mechanism involves three paths leading to three main different products: oxirane, ethanal, and nitric acid. The three paths start from the same initial intermediate, an NO(3)-ethene adduct. The calculated energy barriers show that the oxirane is the product kinetically more favored. Initial analysis of the potential energy surface was made at AM1 level. Then, the geometries and characterization of the found stationary points on the surface were refined at ROHF level with a 6-31G basis set. Further refinement was carried out at CASSCF level with the same basis set, and an active space was built with five active electrons in six active orbitals.
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de Castilla-La Mancha, Campus Universitario 13071, Ciudad Real, Spain.
authors.forename: M. Pilar
authors.initials: MP
authors.lastname: Pérez-Casany
authors.forename: Ignacio
authors.initials: I
authors.lastname: Nebot-Gil
authors.forename: José
authors.initials: J
authors.lastname: Sánchez-Marín
authors.forename: Francisco
authors.initials: F
authors.lastname: Tomás-Vert
authors.forename: Ernesto
authors.initials: E
authors.lastname: Martínez-Ataz
authors.forename: Beatriz
authors.initials: B
authors.lastname: Cabañas-Galán
authors.forename: Alfonso
authors.initials: A
authors.lastname: Aranda-Rubio