Materials Data on KBe2B3O7 by Materials Project
KBe2B3O7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.84–3.01 Å. In the second K1+ site, K1+ is bonded in a 2-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.83–3.33 Å. In the third K1+ site, K1+ is bonded to eight O2- atoms to form distorted KO8 hexagonal bipyramids that share corners with four BeO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.80–3.16 Å. There are six inequivalent Be2+ sites. In the first Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and corners with three BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.65–1.68 Å. In the second Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and corners with three BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.64–1.67 Å. In the third Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and corners with three BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.63–1.67 Å. In the fourth Be2+ site, Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and corners with three BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.62–1.68 Å. In the fifth Be2+ site, Be2+ is bonded to four O2- atoms to form corner-sharing BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.62–1.67 Å. In the sixth Be2+ site, Be2+ is bonded to four O2- atoms to form corner-sharing BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.59–1.67 Å. There are nine inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.38 Å) and one longer (1.39 Å) B–O bond length. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.38 Å) and one longer (1.39 Å) B–O bond length. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.38 Å) and two longer (1.39 Å) B–O bond length. In the fourth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.34–1.42 Å. In the fifth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.31 Å) and two longer (1.42 Å) B–O bond length. In the sixth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.34–1.42 Å. In the seventh B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.32 Å) and two longer (1.42 Å) B–O bond length. In the eighth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.34–1.42 Å. In the ninth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.34–1.42 Å. There are twenty-one inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one K1+, two Be2+, and one B3+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to two Be2+ and one B3+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to two Be2+ and one B3+ atom. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to one K1+, two Be2+, and one B3+ atom. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to one K1+, two Be2+, and one B3+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to one K1+, two Be2+, and one B3+ atom. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to two Be2+ and one B3+ atom. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to two Be2+ and one B3+ atom. In the ninth O2- site, O2- is bonded in a trigonal planar geometry to one K1+, two Be2+, and one B3+ atom. In the tenth O2- site, O2- is bonded in a distorted linear geometry to one K1+, one Be2+, and one B3+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two B3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+ and two B3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one Be2+, and one B3+ atom. In the fourteenth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one Be2+, and one B3+ atom. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two K1+, one Be2+, and one B3+ atom. In the seventeenth O2- site, O2- is bonded in a bent 120 degrees geometry to two K1+ and two B3+ atoms. In the eighteenth O2- site, O2- is bonded in a bent 120 degrees geometry to two K1+ and two B3+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one Be2+, and one B3+ atom. In the twentieth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two K1+, one Be2+, and one B3+ atom.