Volume dependence of the dielectric properties of amorphous SiO2Electronic supplementary information (ESI) available. See DOI: 10.1039/c5cp06775h

Using first principles calculations, the analysis of the dielectric properties of amorphous SiO 2 (am-SiO 2 ) was performed. We found that the am-SiO 2 properties are volume dependent, and the dependence is mainly induced by the variation of nanoporosity at the atomic scale. In particular, both ionic and electronic contributions to the static dielectric constants are functions of volume with clear trends. Moreover, using the unique parameterization of the dielectric function provided in this work, we predict dielectric functions at imaginary frequencies of different SiO 2 polymorphs having similar band gap energies. The dielectric properties of amorphous SiO 2 and other SiO 2 polymorphs are linked by simple volume dependence.