DOI: 10.17188/1722215
title: Materials Data on Ca4Ti4Si3GeO20 by Materials Project

description: Ca4Ti4GeSi3O20 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.58 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.27–2.67 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.68 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.65 Å. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, a cornercorner with one GeO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–39°. There are a spread of Ti–O bond distances ranging from 1.81–2.06 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, a cornercorner with one GeO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–38°. There are a spread of Ti–O bond distances ranging from 1.82–2.04 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, a cornercorner with one GeO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–38°. There are a spread of Ti–O bond distances ranging from 1.81–2.04 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, a cornercorner with one GeO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–39°. There are a spread of Ti–O bond distances ranging from 1.80–2.05 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 40–57°. All Ge–O bond lengths are 1.77 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 four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 35–54°. All Si–O bond lengths are 1.65 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 34–53°. There is two shorter (1.65 Å) and two longer (1.66 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 35–53°. There are a spread of Si–O bond distances ranging from 1.64–1.66 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Ti4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Ti4+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Ti4+ atoms. In the fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Ti4+, and one Ge4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded to two Ca2+, one Ti4+, and one Ge4+ atom to form distorted corner-sharing OCa2TiGe tetrahedra. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded to two Ca2+, one Ti4+, and one Ge4+ atom to form distorted corner-sharing OCa2TiGe tetrahedra. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Ge4+ atom.