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

Auteur(s): Haines Julien, Cambon Olivier, Levelut C., Santoro Mario, Gorelli Federico, Gabarino Gaston

(Article) Publié: Journal Of The American Chemical Society, vol. 132 p.8860–8861 (2010)


Ref HAL: hal-00498156_v1
PMID 20540493
DOI: 10.1021/ja1034599
WoS: 000279561200023
Exporter : BibTex | endNote
78 Citations
Résumé:

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.