Materials Data on SrCa2(TeO3)3 by Materials Project
SrCa2(TeO3)3 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.78 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.36–2.68 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.26–2.60 Å. There are three inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–2.72 Å. In the second Te4+ site, Te4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.88 Å) and one longer (1.89 Å) Te–O bond length. In the third Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is one shorter (1.89 Å) and two longer (1.90 Å) Te–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, one Ca2+, and one Te4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and one Te4+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Sr2+, two Ca2+, and one Te4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two Te4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Ca2+, and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ca2+ and one Te4+ atom. In the seventh O2- site, O2- is bonded to one Sr2+, two Ca2+, and one Te4+ atom to form distorted corner-sharing OSrCa2Te trigonal pyramids. In the eighth O2- site, O2- is bonded to two equivalent Sr2+, one Ca2+, and one Te4+ atom to form distorted OSr2CaTe tetrahedra that share corners with two equivalent OSr2CaTe tetrahedra and corners with three equivalent OSrCa2Te trigonal pyramids. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one Te4+ atom.