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