Materials Data on SiO2 by Materials Project
SiO2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Si4+ is bonded to four O2- atoms to form distorted corner-sharing SiO4 trigonal pyramids. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms.