Materials Data on K2Si6GeO15 by Materials Project
K2GeSi6O15 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.70–3.32 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.77–3.16 Å. Ge4+ is bonded to six O2- atoms to form GeO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Ge–O bond distances ranging from 1.89–1.94 Å. There are six inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one GeO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 32°. There are a spread of Si–O bond distances ranging from 1.59–1.66 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one GeO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one GeO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one GeO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one GeO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one GeO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. There are a spread of Si–O bond distances ranging from 1.60–1.65 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one K1+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ge4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ge4+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ge4+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ge4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ge4+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one Ge4+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms.