Materials Data on SiO2 by Materials Project
SiO2 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There is one shorter (1.63 Å) and three longer (1.64 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There is two shorter (1.62 Å) and two longer (1.64 Å) Si–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms.