(17)O NMR Investigation of Water Structure and Dynamics.
(17)O NMR Investigation of Water Structure and Dynamics.
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(17)水结构和动力学的O NMR研究。
DOI：
10.1021/acs.jpcb.6b05755
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Griffin,RobertG
中科院分区：
文献类型：
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作者：
Keeler,EricG;Michaelis,VladimirK;Griffin,RobertG
在14.1 ~ 21.1T的磁场中，用17 O核磁共振（NMR）谱研究了一水氯酸钡中束缚水的结构和动力学，测定了水的17 O NMR参数，用变温MAS NMR研究了水分子的扭振对17 O四极耦合常数（CQ）的影响。随着温度的降低和减少的librational运动，我们观察到增加的实验measuredCQ解释从密度泛函理论的实验和预测之间的差异。此外，在低温下，在没有1H去偶的情况下，我们观察到一个很好的解析1H-17 O偶极分裂的光谱，这提供了信息的H2O分子的结构。分裂的出现是因为两个1H-17 O偶极子和1H-1H偶极子之间的耦合的均匀性。
The structure and dynamics of the bound water in barium chlorate monohydrate were studied with17O nuclear magnetic resonance (NMR) spectroscopy in samples that are stationary and spinning at the magic-angle in magnetic fields ranging from 14.1 to 21.1 T.17O NMR parameters of the water were determined, and the effects of torsional oscillations of the water molecule on the17O quadrupolar coupling constant (CQ) were delineated with variable temperature MAS NMR. With decreasing temperature and reduction of the librational motion, we observe an increase in the experimentally measuredCQexplaining the discrepancy between experiments and predictions from density functional theory. In addition, at low temperatures and in the absence of1H decoupling, we observe a well-resolved1H–17O dipole splitting in the spectra, which provides information on the structure of the H2O molecule. The splitting arises because of the homogeneous nature of the coupling between the two1H–17O dipoles and the1H–1H dipole.