Materials Data on K2Ca2(SO4)3 by Materials Project

Abstract

K2Ca2(SO4)3 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.94–3.35 Å. In the second K1+ site, K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.76–3.42 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six SO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.33–2.42 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six SO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.33–2.37 Å. There are three inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four CaO6 octahedra. The corner-sharing octahedra tilt angles range from 17–51°. There is one shorter (1.48 Å) and three longer (1.49 Å) S–O bond length. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four CaO6 octahedra. The corner-sharing octahedra tilt angles range from 24–50°. All S–O bond lengths are 1.49 Å. In the third S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four CaO6 octahedra. The corner-sharing octahedra tilt angles range from 31–58°. All S–O bond lengths are 1.49 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ca2+, and one S6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Ca2+, and one S6+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ca2+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ca2+, and one S6+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Ca2+, and one S6+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ca2+, and one S6+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ca2+, and one S6+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ca2+, and one S6+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Ca2+, and one S6+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ca2+, and one S6+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ca2+, and one S6+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Ca2+, and one S6+ atom.