Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark.
J Phys Chem A. 2011 Aug 11;115(31):8669-81. doi: 10.1021/jp203907d. Epub 2011 Jul 15.
We have studied the oxidation of SO(2) to SO(3) by four peroxyradicals and two carbonyl oxides (Criegee intermediates) using both density functional theory, B3LYP, and explicitly correlated coupled cluster theory, CCSD(T)-F12. All the studied peroxyradicals react very slowly with SO(2) due to energy barriers (activation energies) of around 10 kcal/mol or more. We find that water molecules are not able to catalyze these reactions. The reaction of stabilized Criegee intermediates with SO(2) is predicted to be fast, as the transition states for these oxidation reactions are below the free reactants in energy. The atmospheric relevance of these reactions depends on the lifetimes of the Criegee intermediates, which, at present, is highly uncertain.
我们使用密度泛函理论 B3LYP 和显式相关耦合簇理论 CCSD(T)-F12 研究了四种过氧自由基和两种羰基氧化物（克里格中间体）将 SO(2)氧化为 SO(3)的过程。所有研究的过氧自由基由于约 10 千卡/摩尔或更高的能垒（活化能），与 SO(2)的反应非常缓慢。我们发现水分子不能催化这些反应。稳定的克里格中间体与 SO(2)的反应预计是快速的，因为这些氧化反应的过渡态在能量上低于游离反应物。这些反应的大气相关性取决于克里格中间体的寿命，目前这一点高度不确定。
