Molecular properties affecting the hydration of acid–base clusters
Molecular properties affecting the hydration of acid–base clusters
复制标题
影响酸碱簇水合的分子特性
DOI：
10.1039/d1cp01704g
复制
发表时间：
2021
影响因子：
3.3
通讯作者：
Smith, James N.
中科院分区：
文献类型：
--
作者：
Myllys, Nanna;Myers, Deanna;Chee, Sabrina;Smith, James N.
在大气中，水在大气中无处不在，在催化大气化学反应、参与团簇形成和影响气溶胶粒子组成等方面发挥着重要作用。对含水星团的直接测量是有限的，因为水很可能在检测之前蒸发，因此，需要理论工具来研究大气中的水合作用。我们研究了与大气相关的不同碱性单体以及硫酸-碱对的水化热力学和布居动力学。碱的水化能力似乎遵循气相碱强度的顺序，而酸碱对的水化能力，从而团簇的水化能力，与氢结合位的数量有关。水-气界面上的质子转移反应在许多环境和生物系统中是重要的，但对其机理的更深层次的了解仍然难以捉摸。通过对含有多达20个水分子和一个碱基分子的团簇中质子转移反应的热力学研究，我们发现碱在水团簇中接受质子的能力与水相碱性有关。我们还研究了硫酸在水合酸碱簇合物中的二次去质子化反应，发现在二甲胺存在下，硫酸盐的生成最有利。讨论了与水团簇中质子转移能力有关的分子性质。
In the atmosphere, water in all phases is ubiquitous and plays important roles in catalyzing atmospheric chemical reactions, participating in cluster formation and affecting the composition of aerosol particles. Direct measurements of water-containing clusters are limited because water is likely to evaporate before detection, and therefore, theoretical tools are needed to study hydration in the atmosphere. We have studied thermodynamics and population dynamics of the hydration of different atmospherically relevant base monomers as well as sulfuric acid–base pairs. The hydration ability of a base seems to follow in the order of gas-phase base strength whereas hydration ability of acid–base pairs, and thus clusters, is related to the number of hydrogen binding sites. Proton transfer reactions at water–air interfaces are important in many environmental and biological systems, but a deeper understanding of their mechanisms remain elusive. By studying thermodynamics of proton transfer reactions in clusters containing up to 20 water molecules and a base molecule, we found that that the ability of a base to accept a proton in a water cluster is related to the aqueous-phase basicity. We also studied the second deprotonation reaction of a sulfuric acid in hydrated acid–base clusters and found that sulfate formation is most favorable in the presence of dimethylamine. Molecular properties related to the proton transfer ability in water clusters are discussed.