水溶性酸,碱,盐溶液表面统一的分子图像

2008/04/26   下载量: 70

方案摘要

方案下载
应用领域 石油/化工
检测样本 基础有机原料
检测项目
参考标准 暂无

The molecular structure of the interfacial regions of aqueous electrolytes is poorly understood, despite its crucial importance in many biological, technological, and atmospheric processes. A long-term controversy pertains between the standard picture of an ion-free surface layer and the strongly ion specific behavior indicating in many cases significant propensities of simple inorganic ions for the interface. Here, we present a unified and consistent view of the structure of the air/solution interface of aqueous electrolytes containing monovalent inorganic ions. Molecular dynamics calculations show that in salt solutions and bases the positively charged ions, such as alkali cations, are repelled from the interface, whereas the anions, such as halides or hydroxide, exhibit a varying surface propensity, correlated primarily with the ion polarizability and size. The behavior of acids is different due to a significant propensity of hydronium cations for the air/solution interface. Therefore, both cations and anions exhibit enhanced concentrations at the surface and, consequently, these acids (unlike bases and salts) reduce the surface tension of water. The results of the simulations are supported by surface selective nonlinear vibrational spectroscopy(VSFG), which reveals among other things that the hydronium cations are present at the air/solution interface. The ion specific propensities for the air/solution interface have important implications for a whole range of heterogeneous physical and chemical processes, including atmospheric chemistry of aerosols, corrosion processes, and bubble coalescence.

方案下载
配置单
上一篇 在一个双稳湍流涡旋火焰中,对间歇性动态的时间-频率定位
下一篇 空气/水界面和频产生(SFG)振动光谱的偏振特性和实验装置分析

文献贡献者

相关仪器 更多
相关方案
更多

相关产品

当前位置: 欧兰科技 方案 水溶性酸,碱,盐溶液表面统一的分子图像

关注

拨打电话

留言咨询