Materials Data on Ca5(GeO5)2 by Materials Project

Abstract

Ca5(GeO5)2 is beta indium sulfide-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Ca sites. In the first Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with four equivalent CaO6 octahedra, corners with two equivalent GeO4 tetrahedra, edges with four CaO6 octahedra, and edges with two equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 63–64°. There are a spread of Ca–O bond distances ranging from 2.37–2.41 Å. In the second Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with eight CaO6 octahedra, corners with three equivalent GeO4 tetrahedra, edges with two CaO6 octahedra, and an edgeedge with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–64°. There are a spread of Ca–O bond distances ranging from 2.33–2.50 Å. In the third Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six CaO6 octahedra, corners with two equivalent GeO4 tetrahedra, edges with three CaO6 octahedra, and an edgeedge with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–66°. There are a spread of Ca–O bond distances ranging from 2.30–2.47 Å. Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with six CaO6 octahedra and edges with three CaO6 octahedra. The corner-sharing octahedra tilt angles range from 54–61°. There is one shorter (1.76 Å) and three longer (1.80 Å) Ge–O bond length. There are five inequivalent O sites. In the first O site, O is bonded in a rectangular see-saw-like geometry to three Ca and one Ge atom. In the second O site, O is bonded in a rectangular see-saw-like geometry to three Ca and one Ge atom. In the third O site, O is bonded in a rectangular see-saw-like geometry to three Ca and one Ge atom. In the fourth O site, O is bonded to three Ca and one Ge atom to form distorted corner-sharing OCa3Ge tetrahedra. In the fifth O site, O is bonded in a distorted trigonal planar geometry to three Ca atoms.