Infrared photodissociation spectroscopy of [Mg·(H2O) 1-4]+ and [Mg·(H2O) 1-4·Ar]+
Infrared photodissociation spectroscopy of [Mg·(H2O) 1-4]+ and [Mg·(H2O) 1-4·Ar]+
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[Mg·(H2O) 1-4]+ 和 [Mg·(H2O) 1-4·Ar]+ 的红外光解光谱
DOI：
10.1021/jp0486752
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发表时间：
2004
影响因子：
2.9
通讯作者：
N. Nishi
中科院分区：
文献类型：
--
作者：
Y. Inokuchi;K. Ohshimo;F. Misaizu;N. Nishi
测量了[Mg·（H2O）1-4]+和[Mg·（H2O）1-4·Ar]+在3000 ~ 3800 cm-1范围内的红外光解光谱。对于[Mg·（H2O）1-4]+，优化了簇的几何形状，并通过密度泛函理论计算计算了振动频率。通过红外光解光谱与优化后[Mg·（H2O）1-4]+的红外光谱对比，确定了[Mg·（H2O）1-4]+的团簇结构。在[Mg·（H2O）1-3]+离子中，所有的水分子都直接与Mg+离子结合。[Mg·（H2O）4]+和[Mg·（H2O）4·Ar]+的红外光解光谱在3000 ~ 3450 cm-1区域显示氢键OH拉伸振动的条带。在[Mg·（H2O）4]+离子中，三个水分子附着在Mg+离子上，形成第一溶剂化壳层；第四个分子连着第一个溶剂化层。结果，[Mg·（H2O）4]+最稳定的同分异构体有一个由Mg+离子组成的六元环，在第一次溶剂化中，三个水分子中的两个是由Mg+离子组成的。
Infrared photodissociation spectra of [Mg·(H2O)1-4]+ and [Mg·(H2O)1-4·Ar]+ are measured in the 3000−3800 cm-1 region. For [Mg·(H2O)1-4]+, cluster geometries are optimized and vibrational frequencies are evaluated by density functional theory calculation. We determine cluster structures of [Mg·(H2O)1-4]+ by comparison of the infrared photodissociation spectra with infrared spectra calculated for optimized structures of [Mg·(H2O)1-4]+. In the [Mg·(H2O)1-3]+ ions, all the water molecules are directly bonded to the Mg+ ion. The infrared photodissociation spectra of [Mg·(H2O)4]+ and [Mg·(H2O)4·Ar]+ show bands due to hydrogen-bonded OH stretching vibrations in the 3000−3450 cm-1 region. In the [Mg·(H2O)4]+ ion, three water molecules are attached to the Mg+ ion, forming the first solvation shell; the fourth molecule is bonded to the first solvation shell. As a result, the most stable isomer of [Mg·(H2O)4]+ has a six-membered ring composed of the Mg+ ion, two of the three water molecules in the first solvation sh...