Aqueous Redox Chemistry and the Electronic Band Structure of Liquid Water
Aqueous Redox Chemistry and the Electronic Band Structure of Liquid Water
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DOI：
10.1021/jz3015293
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发表时间：
2012-12-06
影响因子：
5.7
通讯作者：
Sprik, Michiel
中科院分区：
文献类型：
--
作者：
Adriaanse, Christopher;Cheng, Jun;Sprik, Michiel
如果含水物质的电子态在能量上接近水的带边，则它们可以与溶剂的扩展态混合。使用基于密度泛函理论的分子动力学模拟，我们表明，这是OH-和Cl-的情况。然而，这种效果被严重夸大的广义梯度近似导致系统低估的氧化还原电位和虚假的非线性溶剂重组。绘制一个平行的宽禁带固体氧化物中的带电缺陷，我们得出结论，水的价带的错位是错误的主要来源，把OH-和Cl-的氧化还原水平的共振杂质状态。另一方面，对应于强负氧化还原电位的能级能量的准确性是可以接受的。因此，我们预测，混合的垂直附着水平的CO2和未被占用的状态的水是一个真实的效果。
The electronic states of aqueous species can mix with the extended states of the solvent if they are close in energy to the band edges of water. Using density functional theory-based molecular dynamics simulation, we show that this is the case for OH- and Cl-. The effect is, however, badly exaggerated by the generalized gradient approximation leading to systematic underestimation of redox potentials and spurious nonlinearity in the solvent reorganization. Drawing a parallel to charged defects in wide gap solid oxides, we conclude that misalignment of the valence band of water is the main source of error turning the redox levels of OH- and Cl- in resonant impurity states. On the other hand, the accuracy of energies of levels corresponding to strongly negative redox potentials is acceptable. We therefore predict that mixing of the vertical attachment level of CO2 and the unoccupied states of water is a real effect.