Materials Data on K2Be2(SiO3)3 by Materials Project

Abstract

K2Be2(SiO3)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.79–3.24 Å. In the second 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 2.72–3.23 Å. There are two inequivalent Be2+ sites. In the first Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share corners with four SiO4 tetrahedra and an edgeedge with one BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.59–1.71 Å. In the second Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share corners with four SiO4 tetrahedra and an edgeedge with one BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.59–1.72 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two SiO4 tetrahedra and corners with three BeO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two BeO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two SiO4 tetrahedra and corners with three BeO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Be2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, two equivalent Be2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+, one Be2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent K1+, one Be2+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to one K1+, two equivalent Be2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Be2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two Si4+ atoms.