Quantitative Description of Hydrogen Bonding in Chloride−Water Clusters
Quantitative Description of Hydrogen Bonding in Chloride−Water Clusters
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DOI：
10.1021/jp960779s
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发表时间：
1996-06
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影响因子：
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通讯作者：
S. Xantheas
中科院分区：
文献类型：
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作者：
S. Xantheas
我们从第一性原理计算确定了Cl-(H2O)n，n=1−4，团簇的最佳结构、简谐振动频率和增量缔合热，并分析了它们的结构、光谱和能量随团簇尺寸的变化趋势。我们发现，水分子之间的氢键在决定最佳构型方面起着重要作用，因为随着团簇的增长，氢键与氯−水相互作用的竞争变得更加激烈。不同氢键网络之间的竞争导致n=3和4团簇呈现不同的结构、光谱和能量特征的不止一个异构体。水分子间存在较少有序性的构型与较宽、强度较低的红外光谱相关联。相反，强度更大的更窄的带是更有序的配置的特征。最活跃的红外谱带对应于与离子H原子键合的氢沿或垂直于离子H原子的运动。
We have determined the optimal structures, harmonic vibrational frequencies, and incremental association enthalpies for the Cl-(H2O)n, n = 1−4, clusters from first principle calculations and analyzed their structural, spectral, and energetic trends with cluster size. We have found that hydrogen bonding among water molecules plays a significant role in determining the optimal configurations as it becomes more competitive with the chloride−water interaction as the cluster grows. The competition between the different hydrogen bonding networks gives rise to more than one isomer for the n = 3 and 4 clusters that exhibit different structural, spectral, and energetic features. Configurations in which there exists less ordering among water molecules are associated with broader, less intense IR bands. In contrast, narrower bands of larger intensity are signatures of more ordered configurations. The most IR active bands correspond to the motion of the hydrogen bonded to the ion H atom along or perpendicular to the ...