Electronic structure of the water dimer cation
Electronic structure of the water dimer cation
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DOI：
10.1021/jp802140c
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发表时间：
2008-07-10
影响因子：
2.9
通讯作者：
Bradforth, Stephen E.
中科院分区：
文献类型：
--
作者：
Pieniazek, Piotr A.;VandeVondele, Joost;Bradforth, Stephen E.
研究了水二聚体阳离子中质子转移的光谱特征。用电离体系的单取代和双取代的运动方程耦合簇方法，沿着反应坐标表征了六个最低的电子态。中解释了二聚体状态的性质。使用定性分子轨道框架的单体状态的术语。我们发现质子转移引起了电子光谱的显著变化，因此时间分辨电子飞秒光谱是监测电离动力学的一种有效手段。垂直组态和质子转移组态的电子光谱既包括局域激发(与单体相似的特征C)，也包括电荷转移带。用从头算方法检验了密度泛函理论(DFT)的自相互作用修正的性能。修正后的DFT/BLYP方法能够定量地再现(H2O)(2)(+)异构体的正确能量有序性，是较大体系计算的合理途径。
The spectroscopic signatures of proton transfer in the water dimer cation were investigated. The six lowest electronic states were characterized along the reaction coordinate using the equation-of-motion coupled-Cluster with single and double substitutions method for ionized systems. The nature of the dimer states was explained in. terms of the monomer states using a qualitative molecular orbital framework. We found that proton transfer induces significant changes in the electronic spectrum, thus Suggesting that time-resolved electronic femtosecond spectroscopy is an effective strategy to monitor the dynamics following ionization. The electronic spectra at vertical and proton-transferred configurations include both local exitations (features C similar to those of the monomers) and charge-transfer bands. Ab initio calculations were used to test the performance of a self-interaction correction for density functional theory (DFT). The corrected DFT/BLYP method is capable of quantitatively reproducing the proper energetic ordering of the (H2O)(2)(+) isomers and thus is a reasonable approach for calculations of larger systems.