Materials Data on Ca4Ge3O11 by Materials Project
Ca4Ge3O11 is Esseneite-derived structured and crystallizes in the orthorhombic Ama2 space group. The structure is three-dimensional. there are six inequivalent Ca sites. In the first Ca site, Ca is bonded to seven O atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent GeO4 tetrahedra, edges with four CaO6 octahedra, and edges with two equivalent GeO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.34–2.52 Å. In the second Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.90 Å. In the third Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six GeO4 tetrahedra and edges with four CaO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.35–2.48 Å. In the fourth Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.79 Å. In the fifth Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share a cornercorner with one CaO6 octahedra, corners with five GeO4 tetrahedra, edges with two CaO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 29°. There are a spread of Ca–O bond distances ranging from 2.25–2.48 Å. In the sixth Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share a cornercorner with one CaO6 octahedra, corners with five GeO4 tetrahedra, edges with two CaO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 50°. There are a spread of Ca–O bond distances ranging from 2.33–2.44 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with four CaO6 octahedra and corners with two GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–69°. There are a spread of Ge–O bond distances ranging from 1.74–1.84 Å. In the second Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with four CaO6 octahedra, a cornercorner with one CaO7 pentagonal bipyramid, and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–67°. There are a spread of Ge–O bond distances ranging from 1.75–1.81 Å. In the third Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with five CaO6 octahedra, a cornercorner with one GeO4 tetrahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 53–66°. There are a spread of Ge–O bond distances ranging from 1.75–1.82 Å. There are twelve inequivalent O sites. In the first O site, O is bonded to three Ca and one Ge atom to form a mixture of distorted edge and corner-sharing OCa3Ge tetrahedra. In the second O site, O is bonded in a 3-coordinate geometry to two Ca and one Ge atom. In the third O site, O is bonded in a 3-coordinate geometry to one Ca and two Ge atoms. In the fourth O site, O is bonded in a distorted see-saw-like geometry to three Ca and one Ge atom. In the fifth O site, O is bonded in a trigonal non-coplanar geometry to three Ca atoms. In the sixth O site, O is bonded in a trigonal planar geometry to two Ca and one Ge atom. In the seventh O site, O is bonded in a 4-coordinate geometry to four Ca atoms. In the eighth O site, O is bonded to three Ca and one Ge atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids. In the ninth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two Ge atoms. In the tenth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Ca and one Ge atom. In the eleventh O site, O is bonded to three Ca and one Ge atom to form a mixture of distorted edge and corner-sharing OCa3Ge tetrahedra. In the twelfth O site, O is bonded in a distorted trigonal non-coplanar geometry to two Ca and one Ge atom.