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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on CaTb2O4 by Materials Project

CaTb2O4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.54–2.82 Å. There are two inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing TbO6 octahedra. The corner-sharing octahedra tilt angles range from 51–68°. There are a spread of Tb–O bond distances ranging from 2.19–2.40 Å. In the second Tb3+ site, Tb3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing TbO6 octahedra. The corner-sharing octahedra tilt angles range from 51–68°. There are a spread of Tb–O bond distances ranging from 2.23–2.35 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Ca2+ and three Tb3+ atoms. In the second O2- site, O2- is bonded to two equivalent Ca2+ and three equivalent Tb3+ atoms to form a mixture of distorted corner and edge-sharing OCa2Tb3 trigonal bipyramids. In the third O2- site, O2- is bonded to two equivalent Ca2+ and three equivalent Tb3+ atoms to form a mixture of corner and edge-sharing OCa2Tb3 square pyramids. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Ca2+ and three Tb3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaTb2O4 by Materials Project

CaTb2O4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ca2+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–3.02 Å. Tb3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing TbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. There are a spread of Tb–O bond distances ranging from 2.24–2.38 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted square co-planar geometry to two equivalent Ca2+ and four equivalent Tb3+ atoms. In the second O2- site, O2- is bonded to two equivalent Ca2+ and three equivalent Tb3+ atoms to form distorted OCa2Tb3 trigonal bipyramids that share corners with five equivalent OCa2Tb2 tetrahedra, corners with two equivalent OCa2Tb3 trigonal bipyramids, an edgeedge with one OCa2Tb2 tetrahedra, and edges with five equivalent OCa2Tb3 trigonal bipyramids. In the third O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Tb3+ atoms to form OCa2Tb2 tetrahedra that share corners with two equivalent OCa2Tb2 tetrahedra, corners with ten equivalent OCa2Tb3 trigonal bipyramids, and edges with two equivalent OCa2Tb3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaTb2O4 by Materials Project

CaTb2O4 is Spinel structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Ca2+ is bonded to four equivalent O2- atoms to form CaO4 tetrahedra that share corners with twelve equivalent TbO6 octahedra. The corner-sharing octahedra tilt angles range from 58–60°. All Ca–O bond lengths are 2.32 Å. Tb3+ is bonded to six equivalent O2- atoms to form TbO6 octahedra that share corners with six equivalent CaO4 tetrahedra and edges with six equivalent TbO6 octahedra. There are two shorter (2.31 Å) and four longer (2.32 Å) Tb–O bond lengths. O2- is bonded to one Ca2+ and three equivalent Tb3+ atoms to form a mixture of distorted corner and edge-sharing OCaTb3 trigonal pyramids.

36 MATERIALS SCIENCE↗