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DOE OSTI · 1718626

Materials Data on Ni11(GeTe2)2 by Materials Project

Abstract

Ni11(GeTe2)2 crystallizes in the tetragonal P4mm space group. The structure is two-dimensional and consists of one Ni11(GeTe2)2 sheet oriented in the (0, 0, 1) direction. there are seven inequivalent Ni sites. In the first Ni site, Ni is bonded to eight Ni, two equivalent Ge, and two equivalent Te atoms to form distorted NiNi8Ge2Te2 cuboctahedra that share corners with four equivalent NiNi8Ge2Te2 cuboctahedra, edges with four equivalent NiNi8Ge4 cuboctahedra, edges with four equivalent GeNi12 cuboctahedra, edges with four equivalent TeNi8 hexagonal bipyramids, edges with four equivalent NiNi4Te5 square pyramids, faces with two equivalent GeNi12 cuboctahedra, faces with ten NiNi8Ge2Te2 cuboctahedra, faces with two equivalent TeNi8 hexagonal bipyramids, and faces with two equivalent NiNi4Te5 square pyramids. There are a spread of Ni–Ni bond distances ranging from 2.50–2.71 Å. Both Ni–Ge bond lengths are 2.49 Å. Both Ni–Te bond lengths are 2.60 Å. In the second Ni site, Ni is bonded in a 10-coordinate geometry to six Ni, two equivalent Ge, and two equivalent Te atoms. There are two shorter (2.51 Å) and four longer (2.62 Å) Ni–Ni bond lengths. Both Ni–Ge bond lengths are 2.51 Å. Both Ni–Te bond lengths are 2.52 Å. In the third Ni site, Ni is bonded in a 10-coordinate geometry to six Ni, two equivalent Ge, and two equivalent Te atoms. There are two shorter (2.51 Å) and four longer (2.62 Å) Ni–Ni bond lengths. Both Ni–Ge bond lengths are 2.51 Å. Both Ni–Te bond lengths are 2.50 Å. In the fourth Ni site, Ni is bonded in a 10-coordinate geometry to six Ni, two equivalent Ge, and two equivalent Te atoms. There are two shorter (2.50 Å) and four longer (2.62 Å) Ni–Ni bond lengths. Both Ni–Ge bond lengths are 2.51 Å. Both Ni–Te bond lengths are 2.51 Å. In the fifth Ni site, Ni is bonded to eight Ni and four equivalent Ge atoms to form NiNi8Ge4 cuboctahedra that share corners with four equivalent NiNi8Ge4 cuboctahedra, faces with four equivalent NiNi8Ge4 cuboctahedra, and faces with four equivalent GeNi12 cuboctahedra. All Ni–Ge bond lengths are 2.62 Å. In the sixth Ni site, Ni is bonded to eight Ni and four equivalent Ge atoms to form NiNi8Ge4 cuboctahedra that share corners with four equivalent NiNi8Ge4 cuboctahedra, corners with four equivalent TeNi8 hexagonal bipyramids, edges with eight equivalent NiNi8Ge2Te2 cuboctahedra, edges with four equivalent NiNi4Te5 square pyramids, faces with four equivalent GeNi12 cuboctahedra, faces with eight NiNi8Ge2Te2 cuboctahedra, and a faceface with one TeNi8 hexagonal bipyramid. All Ni–Ge bond lengths are 2.62 Å. In the seventh Ni site, Ni is bonded to four equivalent Ni and five Te atoms to form distorted NiNi4Te5 square pyramids that share corners with four equivalent GeNi12 cuboctahedra, corners with four equivalent NiNi4Te5 square pyramids, edges with twelve NiNi8Ge2Te2 cuboctahedra, edges with four equivalent TeNi8 hexagonal bipyramids, a faceface with one GeNi12 cuboctahedra, faces with four equivalent NiNi8Ge2Te2 cuboctahedra, and faces with four equivalent NiNi4Te5 square pyramids. There are one shorter (2.51 Å) and four longer (2.62 Å) Ni–Te bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded to twelve Ni atoms to form GeNi12 cuboctahedra that share corners with four equivalent GeNi12 cuboctahedra, faces with four equivalent NiNi8Ge4 cuboctahedra, and faces with four equivalent GeNi12 cuboctahedra. In the second Ge site, Ge is bonded to twelve Ni atoms to form GeNi12 cuboctahedra that share corners with four equivalent GeNi12 cuboctahedra, corners with four equivalent NiNi4Te5 square pyramids, edges with eight equivalent NiNi8Ge2Te2 cuboctahedra, edges with four equivalent TeNi8 hexagonal bipyramids, faces with four equivalent GeNi12 cuboctahedra, faces with eight NiNi8Ge2Te2 cuboctahedra, and a faceface with one NiNi4Te5 square pyramid. There are four inequivalent Te sites. In the first Te site, Te is bonded to eight Ni atoms to form distorted TeNi8 hexagonal bipyramids that share corners with four equivalent NiNi8Ge4 cuboctahedra, corners with four equivalent TeNi8 hexagonal bipyramids, edges with four equivalent GeNi12 cuboctahedra, edges with eight equivalent NiNi8Ge2Te2 cuboctahedra, edges with four equivalent NiNi4Te5 square pyramids, faces with five NiNi8Ge2Te2 cuboctahedra, and faces with four equivalent TeNi8 hexagonal bipyramids. In the second Te site, Te is bonded in a 4-coordinate geometry to four equivalent Ni atoms. In the third Te site, Te is bonded in a 5-coordinate geometry to five Ni atoms. In the fourth Te site, Te is bonded in a 4-coordinate geometry to four equivalent Ni atoms.

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2020-04-30. Materials Data on Ni11(GeTe2)2 by Materials Project. https://doi.org/10.17188/1718626

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