Proton environments and hydrogen-bonding in hydrous silicate glasses from proton NMR
Proton environments and hydrogen-bonding in hydrous silicate glasses from proton NMR
复制标题
来自质子 NMR 的质子环境和水合硅酸盐玻璃中的氢键
DOI：
10.1038/337539a0
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发表时间：
1989
期刊：
影响因子：
64.8
通讯作者：
Mark E. Smith
中科院分区：
文献类型：
--
作者：
S. Kohn;R. Dupree;Mark E. Smith
水在岩浆中的溶解对岩浆的物理和化学性质有着深远的影响，对这一过程的理解在火成岩岩石学和地球化学中仍然具有重要意义。对含水熔体物理性质的系统研究，以及对熔体淬火玻璃的红外1，2，拉曼2，3和29Si NMR 4光谱研究，提供了有价值的信息，但仍有许多问题没有得到解答。以前对玻璃的质子NMR研究一般集中在线形上，以区分Si-OH基团和分子H2O中的质子环境（参考文献5，6）。在这里，我们提出的质子NMR结果在玻璃淬火从含水熔体，这使我们能够解决不同的质子网站的化学位移差异的基础上。四个独立的质子共振在含有8.7重量%的水的二氧化硅玻璃中解决，和一个强氢键Si-OH基团被确定在含水碱金属和碱土金属二硅酸盐玻璃。在二氧化硅玻璃中的水形态的定量估计同意从29Si NMR 4。未来的质子核磁共振测量，解决不同的化学环境将发挥重要作用，在阐明含氢无序固体的结构。
The dissolution of water in magmas has profound effects on their physical and chemical properties, and an understanding of this process continues to be of major importance in igneous petrology and geochemistry. Systematic studies of the physical properties of hydrous melts, and infrared1,2, Raman2,3 and 29Si NMR4 spectro-scopic studies of glasses quenched from melts, have provided valuable information, but many questions remain unanswered. Previous proton NMR studies of glasses have generally concentrated on lineshape, to distinguish between the proton environments in Si–OH groups and in molecular H2O (refs 5, 6). Here we present proton NMR results in glasses quenched from hydrous melts, which allow us to resolve different proton sites on the basis of chemical-shift differences. Four separate proton resonances are resolved in a silica glass containing 8.7 wt% H2O, and a strongly hydrogen-bonded Si–OH group is identified in hydrous alkali and alkaline-earth disilicate glasses. Quantitative estimates of water speciation in the silica glasses agree with those from 29Si NMR4. Future proton NMR measurements which resolve different chemical environments will play an important role in elucidating the structures of hydrogen-bearing disordered solids.