Crystallographic Analysis of SiO2 Polymorphs

Resumo

The crystallographic analysis of six SiO₂ phases (α-quartz, β-tridymite, α- and β-cristobalite, coesite, and stishovite) is performed. The effect of the local symmetry of SiO₄ tetrahedra on the symmetry of phases tending either to highly symmetrical cubic P-cristobalite or hexagonal P-tridymite is shown. The parameters of cation, anion, and joint pseudotranslational sublattices characterizing the atomic configurations of the structures and their individual features are calculated. The relative stability of the phases is considered.