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DOE OSTI · 1736795

Materials Data on K2YbGe4O11 by Materials Project

Abstract

K2YbGe4O11 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are four inequivalent K sites. In the first K site, K is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of K–O bond distances ranging from 2.81–2.90 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.80–2.98 Å. In the third K site, K is bonded in a 6-coordinate geometry to four O atoms. There are two shorter (2.79 Å) and two longer (2.93 Å) K–O bond lengths. In the fourth K site, K is bonded in a 5-coordinate geometry to five O atoms. There are a spread of K–O bond distances ranging from 2.66–3.05 Å. Yb is bonded to six O atoms to form YbO6 octahedra that share corners with two equivalent YbO6 octahedra and corners with four GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 27–46°. There are a spread of Yb–O bond distances ranging from 2.25–2.32 Å. There are four 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 YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Ge–O bond distances ranging from 1.73–1.79 Å. In the second Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Ge–O bond distances ranging from 1.73–1.80 Å. In the third Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Ge–O bond distances ranging from 1.72–1.80 Å. In the fourth Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one YbO6 octahedra and corners with three GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 10°. There are a spread of Ge–O bond distances ranging from 1.72–1.80 Å. There are fourteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one K and two equivalent Ge atoms. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one K and two Ge atoms. In the third O site, O is bonded in a 2-coordinate geometry to one K, one Yb, and one Ge atom. In the fourth O site, O is bonded in a 4-coordinate geometry to two K, one Yb, and one Ge atom. In the fifth O site, O is bonded in a distorted trigonal planar geometry to one K and two equivalent Ge atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one K and two Ge atoms. In the seventh O site, O is bonded in a bent 150 degrees geometry to two equivalent Ge atoms. In the eighth O site, O is bonded in a 4-coordinate geometry to two equivalent K, one Yb, and one Ge atom. In the ninth O site, O is bonded in a bent 120 degrees geometry to two equivalent Ge atoms. In the tenth O site, O is bonded in a bent 150 degrees geometry to two equivalent Yb atoms. In the eleventh O site, O is bonded in a 3-coordinate geometry to one K and two Ge atoms. In the twelfth O site, O is bonded in a 2-coordinate geometry to one K, one Yb, and one Ge atom. In the thirteenth O site, O is bonded in a 2-coordinate geometry to one K and two Ge atoms. In the fourteenth O site, O is bonded in a 4-coordinate geometry to two K and two equivalent Yb atoms.

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2020-04-29. Materials Data on K2YbGe4O11 by Materials Project. https://doi.org/10.17188/1736795

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36 MATERIALS SCIENCE↗