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DOE OSTI · 1277924

Materials Data on Sm3Si2Ni by Materials Project

Abstract

Sm3NiSi2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Sm2+ sites. In the first Sm2+ site, Sm2+ is bonded in a 6-coordinate geometry to one Ni2+ and five Si4- atoms. The Sm–Ni bond length is 2.86 Å. There are four shorter (3.00 Å) and one longer (3.22 Å) Sm–Si bond lengths. In the second Sm2+ site, Sm2+ is bonded to five Si4- atoms to form distorted edge-sharing SmSi5 square pyramids. There are a spread of Sm–Si bond distances ranging from 2.96–3.04 Å. In the third Sm2+ site, Sm2+ is bonded in a 7-coordinate geometry to two equivalent Ni2+ and five Si4- atoms. Both Sm–Ni bond lengths are 2.82 Å. There are a spread of Sm–Si bond distances ranging from 2.95–3.65 Å. Ni2+ is bonded in a 3-coordinate geometry to three Sm2+ and three Si4- atoms. There are one shorter (2.43 Å) and two longer (2.44 Å) Ni–Si bond lengths. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Sm2+ and one Ni2+ atom. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to seven Sm2+ and two equivalent Ni2+ atoms.

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2020-07-23. Materials Data on Sm3Si2Ni by Materials Project. https://doi.org/10.17188/1277924

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