DOE OSTI2020
ScGaO3 crystallizes in the hexagonal P6_3cm space group. The structure is three-dimensional. there are two inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sc–O bond distances ranging from 2.16–2.42 Å. In the second Sc3+ site, Sc3+ is bonded to seven O2- atoms to form distorted ScO7 pentagonal bipyramids that share corners with three equivalent GaO5 trigonal bipyramids and edges with three equivalent GaO5 trigonal bipyramids. There are a spread of Sc–O bond distances ranging from 2.14–2.30 Å. Ga3+ is bonded to five O2- atoms to form GaO5 trigonal bipyramids that share a cornercorner with one ScO7 pentagonal bipyramid, corners with six equivalent GaO5 trigonal bipyramids, and an edgeedge with one ScO7 pentagonal bipyramid. There are a spread of Ga–O bond distances ranging from 1.92–1.96 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Sc3+ and one Ga3+ atom to form OSc3Ga tetrahedra that share corners with ten OSc3Ga tetrahedra, corners with two equivalent OScGa3 trigonal pyramids, edges with three equivalent OSc3Ga tetrahedra, and edges with two equivalent OScGa3 trigonal pyramids. In the second O2- site, O2- is bonded to three Sc3+ and one Ga3+ atom to form distorted OSc3Ga tetrahedra that share corners with ten OSc3Ga tetrahedra, corners with four equivalent OScGa3 trigonal pyramids, edges with three equivalent OSc3Ga tetrahedra, and an edgeedge with one OScGa3 trigonal pyramid. In the third O2- site, O2- is bonded to one Sc3+ and three equivalent Ga3+ atoms to form distorted OScGa3 trigonal pyramids that share corners with six equivalent OSc3Ga tetrahedra, corners with six OScGa3 trigonal pyramids, and edges with three equivalent OSc3Ga tetrahedra. In the fourth O2- site, O2- is bonded to one Sc3+ and three equivalent Ga3+ atoms to form distorted OScGa3 trigonal pyramids that share corners with six equivalent OSc3Ga tetrahedra, corners with six equivalent OScGa3 trigonal pyramids, and edges with three equivalent OSc3Ga tetrahedra.