High Pressure Polymorphism in Silica
نویسندگان
چکیده
Fundamental crystal chemistry and first-principles total-energy calculations are used to examine stable and metastable high-pressure silica structures. We find that a large class of energetically competitive phases can be generated from hcp arrays of oxygen with silicon occupying one-half of the octahedral sites. Calculations for specific structures provide an explanation for a number of recent high-pressure results for crystalline silica and allow us to understand the nature of the shortand intermediate-range order in the high-pressure amorphous state. [S0031-9007(98)05385-X]
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