Materials Data on Si4O9 by Materials Project

Abstract

Si4O9 crystallizes in the tetragonal I4_1/amd space group. The structure is two-dimensional and consists of four Si4O9 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. All Si–O bond lengths are 1.62 Å. In the second Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Si atom. In the second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms.