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The structure of the microporous silica polymorph silicalite was stabilized well beyond the stability range of tetrahedrally coordinated Si[O.sub.2] and the metastability range of low-pressure silica polymorphs such as quartz and cristobalite at room temperature via the incorporation of carbon dioxide or argon. The insertion of guest species deactivates the normal compression and pressure-induced amorphization mechanisms in the silicate material was observed to impede the softening of low-energy vibrations, amorphization, and the eventual increase in silicon coordination up to at least 25 GPa.

A newly developed Monte Carlo (MC) algorithm is designed for studying the complex interplay of dissolution and precipitation reactions on mineral surface. The method is used for understanding the role of the local arrangement of reactive sites and surface topography in the surface evolution during dissolution and the stepwise dissolution has resembled the steady-state dissolution of the quartz-water system.