A theoretical investigation on the mechanism and kinetics of the gas-phase reaction of naphthalene with OH radical

• Published in: Theoretical chemistry accounts 2017-11, Vol.136 (11), p.1-17, Article 131
• Main Authors: Gnanaprakasam, M., Sandhiya, L., Senthilkumar, K.
• Format: Article
• Language: English
• Subjects: Adducts; Atomic/Molecular Structure and Spectra; Biodegradable materials; Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Isomerization; Mathematical analysis; Naphthalene; Naphthol; Nitrogen dioxide; Organic Chemistry; Oxidation; Physical Chemistry; Reaction kinetics; Regular Article; Theoretical and Computational Chemistry
• ISSN: 1432-881X; 1432-2234
• DOI: 10.1007/s00214-017-2162-3

The oxidation of naphthalene initiated by OH radical is studied by using density functional theory methods, M06-2X, ωB97XD and MPWB1K with 6-311G(d,p) basis set. The relative energy of the reactive species is also calculated at CCSD(T)/6-311G(d,p), CCSD(T)/cc-pVDZ, M06-2X/aug-cc-pVTZ and ωB97XD/aug-cc-pVTZ level of theories with the geometry optimized at M06-2X/6-311G(d,p) level of theory. The reactions were found to proceed via electrophilic addition of OH radical to the aromatic ring of naphthalene and H-atom abstraction from the aromatic ring of naphthalene by OH radical. The OH addition and H-atom abstraction reactions are occurring favorably at C1 position of naphthalene. The H-atom abstraction is dominant than OH addition reaction at high temperature (400–873 K). The reactions subsequent to the initial OH radical addition and H-atom abstraction reactions are studied in detail. The reaction of the initially formed intermediates with O 2 results in the formation of peroxy radical and 1-naphthol. The isomerization of peroxy radical and reaction of peroxy radical with HO 2 , NO and NO 2 leads to the formation of epoxynaphthalene, hydroperoxide adducts and nitro naphthalene. We have calculated the rate constant for favorable initial and secondary reactions. This study provides thermochemical and kinetic data for the atmospheric oxidation of naphthalene by OH radical and demonstrates the secondary reactions of naphthalene derivatives.