Near-Infrared Spectroscopy and Anharmonic Theory of Protonated Water Clusters: Higher Elevations in the Hydrogen Bonding Landscape.
Near-Infrared Spectroscopy and Anharmonic Theory of Protonated Water Clusters: Higher Elevations in the Hydrogen Bonding Landscape.
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质子化水团簇的近红外光谱和非调和理论：氢键景观中的更高海拔。
DOI：
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发表时间：
2018
影响因子：
5.7
通讯作者：
Michael A. Duncan
中科院分区：
文献类型：
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作者：
David C. McDonald;J. Wagner;Anne B. McCoy;Michael A. Duncan
近红外光谱测量质子化水簇，H+（H2O）n，在n = 1-8的大小范围内。在脉冲放电超声膨胀中产生团簇，选择质量，并在3600-4550和4850-7350 cm-1的区域中用红外激光光解离光谱进行研究。虽然随着团簇的大小有一些变化，但这些光谱的主要特征是在5300 cm-1附近的宽吸收，在7200 cm-1附近的尖锐双峰，以及在4100 cm-1附近的结构吸收（n ≥ 2）。测得的水合氢，Zundel，和本征离子的振动模式进行比较，由不同形式的非谐理论预测。二阶振动微扰理论（VPT 2）和本地模式治疗的OH拉伸都捕捉光谱的关键方面，但遭受可以理解的缺陷，在定量描述的频带位置和强度。
Near-infrared spectroscopy measurements are presented for protonated water clusters, H+(H2O) n, in the size range of n = 1-8. Clusters are produced in a pulsed-discharge supersonic expansion, mass selected, and studied with infrared laser photodissociation spectroscopy in the regions of 3600-4550 and 4850-7350 cm-1. Although there is some variation with cluster size, the main features of these spectra are a broad absorption near 5300 cm-1, a sharp doublet near 7200 cm-1, as well as a structured absorption near 4100 cm-1 for n ≥ 2. The vibrational patterns measured for the hydronium, Zundel, and Eigen ions are compared to those predicted by different forms of anharmonic theory. Second-order vibrational perturbation theory (VPT2) and a local mode treatment of the OH stretches both capture key aspects of the spectra but suffer understandable deficiencies in the quantitative description of band positions and intensities.