A New Mechanism of Acid Rain Generation from HOSO at the Air–Water Interface

Abstract

The photochemistry of SO 2 at the air− water interface of water droplets leads to the formation of HOSO radicals. Using first-principles simulations, we show that HOSO displays an unforeseen strong acidity (pK a = −1) comparable with that of nitric acid and is fully dissociated at the air−water interface. Accordingly, this radical might play an important role in acid rain formation. Potential implications are discussed.

Photosensitization mechanisms at the air–water interface of aqueous aerosols

“…We use an elaborated computational approach based on the combination of quantum/classical (or QM/MM) molecular dynamics (MD) simulations, 34 and multi-reference configuration interaction (MRCI) ab initio calculations, which has been applied in recent years to analyze interfacial effects on a variety of primary photochemical processes. [35][36][37][38][39][40][41][42][43][44][45][46]…”

Isoprene Reactivity on Water Surfaces from ab initio QM/MM Molecular Dynamics Simulations

“…In this case, and due to the large size of the systems, the geometries have been optimized at the B3LYP/6‐311+G(d) level and the interaction energies have been obtained by single‐point energy calculations at the MP2 level with the same basis set. A similar theoretical approach has been used, together with the 21‐water molecules cluster, to model the adsorption of other systems of atmospheric interest to the water surface . The optimized structures of different complexes are displayed in Figure together with the interaction energies and relevant intermolecular distances.…”

“…A similar theoretical approach has been used, together with the 21-water molecules cluster, to model the adsorption of other systems of atmospheric interest to the water surface. [41,42] The optimized structures of different complexes are displayed in Figure 2 together with the interaction energies and relevant intermolecular distances. The Cartesian coordinates are reported in the SI.…”

“…[5] The interaction of isoprene with a cluster of 21 water molecules was studied at the MP2/6-311 + G(d)//B3LYP/6-311 + G(d) level. The choice of this cluster size was based on the results of previous studies that used it to model interactions with the water surface (see for instance [41,42] ). Different geometries were explored as initial structures, which were chosen on the basis of the results for the 1 : 1 complexes.…”

Research Progress on Photocatalytic/Photoelectrocatalytic Oxidation of Nitrogen Oxides

“…However, the large consumption of fossil fuels, such as coal and petroleum, has led to the excessive emission of nitrogen oxides (NO x ) [1]. The NO x emitted into the atmosphere not only causes acid rain [2,3], photochemical smog [4,5], PM2.5 [6,7], and other environmental problems but also changes the climate and destroys the ozone layer [8]. In addition, NO x severely damages the human heart and lungs and further reduces the efficacy of the human immune system [9], making the human body susceptible to respiratory diseases, such as cough, eye inflammation, chest tightness, nausea, sore throat, and bronchitis [10,11].…”