Materials Data on K6Si2O7 by Materials Project
K6Si2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.67–2.96 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.78–2.97 Å. In the third K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.75–2.93 Å. Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.64–1.70 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to four K1+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to five K1+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to four K1+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to five K1+ and one Si4+ atom.