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DOE OSTI · 1187619

Materials Data on Sm3Sb4Pt7 by Materials Project

Abstract

Sm3Pt7Sb4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Sm+2.67+ sites. In the first Sm+2.67+ site, Sm+2.67+ is bonded to six Pt2- atoms to form SmPt6 octahedra that share corners with two equivalent PtSm4Sb2Pt6 cuboctahedra and edges with two equivalent SmPt6 octahedra. There are four shorter (3.25 Å) and two longer (3.34 Å) Sm–Pt bond lengths. In the second Sm+2.67+ site, Sm+2.67+ is bonded in a 8-coordinate geometry to eight Pt2- atoms. There are a spread of Sm–Pt bond distances ranging from 2.94–3.21 Å. There are four inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a 9-coordinate geometry to four Sm+2.67+, one Pt2-, and four Sb+1.50+ atoms. The Pt–Pt bond length is 2.97 Å. There are a spread of Pt–Sb bond distances ranging from 2.60–2.83 Å. In the second Pt2- site, Pt2- is bonded in a 9-coordinate geometry to three Sm+2.67+, three Pt2-, and three equivalent Sb+1.50+ atoms. All Pt–Pt bond lengths are 2.83 Å. There are two shorter (2.64 Å) and one longer (2.78 Å) Pt–Sb bond lengths. In the third Pt2- site, Pt2- is bonded to four equivalent Sm+2.67+, six Pt2-, and two equivalent Sb+1.50+ atoms to form distorted PtSm4Sb2Pt6 cuboctahedra that share corners with two equivalent SmPt6 octahedra and faces with two equivalent PtSm4Sb2Pt6 cuboctahedra. The corner-sharing octahedral tilt angles are 63°. All Pt–Pt bond lengths are 2.95 Å. Both Pt–Sb bond lengths are 3.04 Å. In the fourth Pt2- site, Pt2- is bonded in a 10-coordinate geometry to two equivalent Sm+2.67+, five Pt2-, and three Sb+1.50+ atoms. There are two shorter (2.72 Å) and one longer (3.00 Å) Pt–Sb bond lengths. There are two inequivalent Sb+1.50+ sites. In the first Sb+1.50+ site, Sb+1.50+ is bonded in a 6-coordinate geometry to six Pt2- atoms. In the second Sb+1.50+ site, Sb+1.50+ is bonded in a 5-coordinate geometry to five Pt2- atoms.

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2020-07-14. Materials Data on Sm3Sb4Pt7 by Materials Project. https://doi.org/10.17188/1187619

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36 MATERIALS SCIENCE↗