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DOE OSTI · 1722536

Materials Data on Hf3ScGa12 by Materials Project

Abstract

ScHf3Ga12 is Uranium Silicide-derived structured and crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. Sc is bonded to twelve Ga atoms to form ScGa12 cuboctahedra that share corners with four equivalent ScGa12 cuboctahedra, corners with four equivalent HfGa12 cuboctahedra, edges with four equivalent HfGa12 cuboctahedra, edges with sixteen GaHf2Sc2Ga8 cuboctahedra, a faceface with one HfGa12 cuboctahedra, faces with four equivalent ScGa12 cuboctahedra, and faces with eight GaHf2Sc2Ga8 cuboctahedra. There are a spread of Sc–Ga bond distances ranging from 2.81–3.05 Å. There are three inequivalent Hf sites. In the first Hf site, Hf is bonded to twelve Ga atoms to form HfGa12 cuboctahedra that share corners with eight HfGa12 cuboctahedra, edges with four equivalent HfGa12 cuboctahedra, edges with sixteen GaHf4Ga8 cuboctahedra, faces with five HfGa12 cuboctahedra, and faces with eight GaHf4Ga8 cuboctahedra. There are a spread of Hf–Ga bond distances ranging from 2.81–3.05 Å. In the second Hf site, Hf is bonded to twelve Ga atoms to form HfGa12 cuboctahedra that share corners with eight HfGa12 cuboctahedra, edges with four equivalent ScGa12 cuboctahedra, edges with sixteen GaHf2Sc2Ga8 cuboctahedra, faces with five HfGa12 cuboctahedra, and faces with eight GaHf4Ga8 cuboctahedra. There are a spread of Hf–Ga bond distances ranging from 2.82–3.06 Å. In the third Hf site, Hf is bonded to twelve Ga atoms to form HfGa12 cuboctahedra that share corners with four equivalent ScGa12 cuboctahedra, corners with four equivalent HfGa12 cuboctahedra, edges with four equivalent HfGa12 cuboctahedra, edges with sixteen GaHf4Ga8 cuboctahedra, a faceface with one ScGa12 cuboctahedra, faces with four equivalent HfGa12 cuboctahedra, and faces with eight GaHf2Sc2Ga8 cuboctahedra. There are a spread of Hf–Ga bond distances ranging from 2.81–3.03 Å. There are eight inequivalent Ga sites. In the first Ga site, Ga is bonded to four Hf and eight Ga atoms to form distorted GaHf4Ga8 cuboctahedra that share corners with twelve GaHf4Ga8 cuboctahedra, edges with eight HfGa12 cuboctahedra, edges with eight GaHf2Sc2Ga8 cuboctahedra, faces with four HfGa12 cuboctahedra, and faces with ten GaHf4Ga8 cuboctahedra. There are a spread of Ga–Ga bond distances ranging from 2.81–2.99 Å. In the second Ga site, Ga is bonded to two equivalent Sc, two equivalent Hf, and eight Ga atoms to form distorted GaHf2Sc2Ga8 cuboctahedra that share corners with twelve GaHf4Ga8 cuboctahedra, edges with four equivalent ScGa12 cuboctahedra, edges with four equivalent HfGa12 cuboctahedra, edges with eight GaHf2Sc2Ga8 cuboctahedra, faces with two equivalent ScGa12 cuboctahedra, faces with two equivalent HfGa12 cuboctahedra, and faces with ten GaHf2Sc2Ga8 cuboctahedra. There are a spread of Ga–Ga bond distances ranging from 2.81–2.95 Å. In the third Ga site, Ga is bonded in a distorted rectangular see-saw-like geometry to four equivalent Hf and eight Ga atoms. All Ga–Ga bond lengths are 2.94 Å. In the fourth Ga site, Ga is bonded in a distorted rectangular see-saw-like geometry to four equivalent Hf and eight Ga atoms. All Ga–Ga bond lengths are 2.99 Å. In the fifth Ga site, Ga is bonded in a distorted rectangular see-saw-like geometry to four equivalent Sc and eight Ga atoms. All Ga–Ga bond lengths are 2.98 Å. In the sixth Ga site, Ga is bonded in a distorted rectangular see-saw-like geometry to four equivalent Hf and eight Ga atoms. All Ga–Ga bond lengths are 2.97 Å. In the seventh Ga site, Ga is bonded to two equivalent Sc, two equivalent Hf, and eight Ga atoms to form GaHf2Sc2Ga8 cuboctahedra that share corners with twelve GaHf2Sc2Ga8 cuboctahedra, edges with four equivalent ScGa12 cuboctahedra, edges with four equivalent HfGa12 cuboctahedra, edges with eight GaHf4Ga8 cuboctahedra, faces with two equivalent ScGa12 cuboctahedra, faces with two equivalent HfGa12 cuboctahedra, and faces with ten GaHf4Ga8 cuboctahedra. All Ga–Ga bond lengths are 2.81 Å. In the eighth Ga site, Ga is bonded to four Hf and eight Ga atoms to form distorted GaHf4Ga8 cuboctahedra that share corners with twelve GaHf2Sc2Ga8 cuboctahedra, edges with eight HfGa12 cuboctahedra, edges with eight GaHf4Ga8 cuboctahedra, faces with four HfGa12 cuboctahedra, and faces with ten GaHf4Ga8 cuboctahedra. All Ga–Ga bond lengths are 2.81 Å.

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2020-04-30. Materials Data on Hf3ScGa12 by Materials Project. https://doi.org/10.17188/1722536

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