Alongi Kristin S, Dibble Theodore S, Shields George C, Kirschner Karl N
Department of Chemistry, Hamilton College, Clinton, New York 13323, USA.
J Phys Chem A. 2006 Mar 16;110(10):3686-91. doi: 10.1021/jp057165k.
The hydroperoxy radical (HO2) plays a critical role in Earth's atmospheric chemistry as a component of many important reactions. The self-reaction of hydroperoxy radicals in the gas phase is strongly affected by the presence of water vapor. In this work, we explore the potential energy surfaces of hydroperoxy radicals hydrogen bonded to one or two water molecules, and predict atmospheric concentrations and vibrational spectra of these complexes. We predict that when the HO2 concentration is on the order of 10(8) molecules x cm(-3) at 298 K, that the number of HO2...H2O complexes is on the order of 10(7) molecules x cm(-3) and the number of HO2...(H2O)2 complexes is on the order of 10(6) molecules x cm(-3). Using the computed abundance of HO2...H2O, we predict that, at 298 K, the bimolecular rate constant for HO2...H2O + HO2 is about 10 times that for HO2 + HO2.
氢过氧自由基（HO2）作为许多重要反应的一个组分，在地球大气化学中起着关键作用。气相中氢过氧自由基的自身反应受到水蒸气存在的强烈影响。在这项工作中，我们探索了与一个或两个水分子形成氢键的氢过氧自由基的势能面，并预测了这些络合物的大气浓度和振动光谱。我们预测，在298 K时，当HO2浓度约为10⁸ 分子·cm⁻³ 时，HO2…H2O络合物的数量约为10⁷ 分子·cm⁻³ ，而HO2…(H2O)2络合物的数量约为10⁶ 分子·cm⁻³ 。利用计算得到的HO2…H2O丰度，我们预测，在298 K时，HO2…H2O + HO2的双分子速率常数约为HO2 + HO2的10倍。
