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DOE OSTI2020

Materials Data on HfGeO4 by Materials Project

HfGeO4 is Zircon-like structured and crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Hf4+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. There are four shorter (2.13 Å) and four longer (2.27 Å) Hf–O bond lengths. Ge4+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All Ge–O bond lengths are 1.79 Å. O2- is bonded in a distorted trigonal planar geometry to two equivalent Hf4+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf3GeO8 by Materials Project

Hf3GeO8 crystallizes in the tetragonal I-42m space group. The structure is three-dimensional. there are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.04 Å) and four longer (2.45 Å) Hf–O bond lengths. In the second Hf4+ site, Hf4+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.18 Å) and four longer (2.22 Å) Hf–O bond lengths. Ge4+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All Ge–O bond lengths are 1.79 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three Hf4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Hf4+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfGeO2 by Materials Project

HfO2(Ge) crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Hf is bonded to six equivalent O atoms to form distorted edge-sharing HfO6 octahedra. There are a spread of Hf–O bond distances ranging from 2.14–2.26 Å. Ge is bonded in a distorted square co-planar geometry to four equivalent O atoms. There are two shorter (2.48 Å) and two longer (2.58 Å) Ge–O bond lengths. O is bonded in a 5-coordinate geometry to three equivalent Hf and two equivalent Ge atoms.

36 MATERIALS SCIENCE↗