Deactivation of Pressure-Induced Amorphization in Silicalite SiO2 by Insertion of Guest Species

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• 作者：Julien Haines ; Olivier Cambon ; Claire Levelut ; Mario Santoro ; Federico Gorelli ; Gaston Garbarino
• 刊名：Journal of the American Chemical Society
• 出版年：2010
• 出版时间：July 7, 2010
• 年：2010
• 卷：132
• 期：26
• 页码：8860-8861
• 全文大小：167K
• 年卷期：v.132,no.26(July 7, 2010)
• ISSN：1520-5126

文摘

The incorporation of carbon dioxide or argon stabilizes the structure of the microporous silica polymorph silicalite well beyond the stability range of tetrahedrally coordinated SiO₂ and, in fact, beyond even the metastability range of low-pressure silica polymorphs such as quartz and cristobalite at room temperature. The bulk modulus of silicalite strongly increases as a result of the incorporation of CO₂ or Ar and is equivalent to that of quartz. The insertion of these species deactivates the normal compression and pressure-induced amorphization mechanisms in this material, impeding the softening of low-energy vibrations, amorphization, and the eventual increase in silicon coordination up to at least 25 GPa.