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DOE OSTI · 1743543

Materials Data on Cd2(GeO3)3 by Materials Project

Abstract

Cd2(GeO3)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Cd sites. In the first Cd site, Cd is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Cd–O bond distances ranging from 2.25–2.40 Å. In the second Cd site, Cd is bonded to six O atoms to form distorted CdO6 octahedra that share corners with five GeO4 tetrahedra, an edgeedge with one CdO6 octahedra, and an edgeedge with one GeO6 octahedra. There are a spread of Cd–O bond distances ranging from 2.27–2.45 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 a cornercorner with one GeO6 octahedra, corners with two equivalent CdO6 octahedra, and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–59°. There are a spread of Ge–O bond distances ranging from 1.74–1.79 Å. In the second Ge site, Ge is bonded to six O atoms to form GeO6 octahedra that share corners with three GeO4 tetrahedra, an edgeedge with one CdO6 octahedra, and an edgeedge with one GeO6 octahedra. There are a spread of Ge–O bond distances ranging from 1.86–1.95 Å. In the third Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent GeO6 octahedra, corners with three equivalent CdO6 octahedra, and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–64°. There is one shorter (1.77 Å) and three longer (1.79 Å) Ge–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Cd and two Ge atoms. In the second O site, O is bonded in a distorted trigonal non-coplanar geometry to one Cd and two Ge atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two Ge atoms. In the fourth O site, O is bonded in a distorted trigonal planar geometry to one Cd and two Ge atoms. In the fifth O site, O is bonded in a water-like geometry to two equivalent Ge atoms. In the sixth O site, O is bonded in a distorted trigonal non-coplanar geometry to two Cd and one Ge atom. In the seventh O site, O is bonded to three Cd and one Ge atom to form distorted edge-sharing OCd3Ge trigonal pyramids. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Cd and one Ge atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to two Cd and one Ge atom.

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2020-06-05. Materials Data on Cd2(GeO3)3 by Materials Project. https://doi.org/10.17188/1743543

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