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DOE OSTI · 1745738

Materials Data on MoPt by Materials Project

Abstract

PtMo crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Mo2+ sites. In the first Mo2+ site, Mo2+ is bonded in a 8-coordinate geometry to eight Pt2- atoms. There are a spread of Mo–Pt bond distances ranging from 2.78–2.84 Å. In the second Mo2+ site, Mo2+ is bonded to eight Pt2- atoms to form distorted MoPt8 hexagonal bipyramids that share corners with eight PtMo8Pt4 cuboctahedra, corners with eight equivalent MoPt8 hexagonal bipyramids, corners with four equivalent MoPt6 octahedra, edges with twelve PtMo8Pt4 cuboctahedra, edges with four equivalent MoPt6 octahedra, faces with two equivalent PtMo6Pt6 cuboctahedra, and faces with four equivalent MoPt6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Mo–Pt bond distances ranging from 2.79–2.84 Å. In the third Mo2+ site, Mo2+ is bonded to six Pt2- atoms to form distorted MoPt6 octahedra that share corners with twelve PtMo8Pt4 cuboctahedra, corners with two equivalent MoPt8 hexagonal bipyramids, corners with seven equivalent MoPt6 octahedra, edges with five PtMo8Pt4 cuboctahedra, edges with two equivalent MoPt8 hexagonal bipyramids, edges with two equivalent MoPt6 octahedra, faces with two equivalent PtMo6Pt6 cuboctahedra, faces with two equivalent MoPt8 hexagonal bipyramids, and a faceface with one MoPt6 octahedra. The corner-sharing octahedra tilt angles range from 3–123°. There are a spread of Mo–Pt bond distances ranging from 2.75–2.84 Å. There are three inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded to eight Mo2+ and four equivalent Pt2- atoms to form PtMo8Pt4 cuboctahedra that share corners with six equivalent PtMo8Pt4 cuboctahedra, corners with four equivalent MoPt8 hexagonal bipyramids, corners with four equivalent MoPt6 octahedra, edges with eight equivalent PtMo6Pt6 cuboctahedra, edges with two equivalent MoPt8 hexagonal bipyramids, edges with two equivalent MoPt6 octahedra, and faces with twelve PtMo8Pt4 cuboctahedra. The corner-sharing octahedral tilt angles are 32°. All Pt–Pt bond lengths are 2.78 Å. In the second Pt2- site, Pt2- is bonded to six Mo2+ and six Pt2- atoms to form PtMo6Pt6 cuboctahedra that share corners with fourteen PtMo6Pt6 cuboctahedra, corners with two equivalent MoPt8 hexagonal bipyramids, corners with six equivalent MoPt6 octahedra, edges with eight PtMo8Pt4 cuboctahedra, edges with three equivalent MoPt8 hexagonal bipyramids, edges with four equivalent MoPt6 octahedra, faces with eight PtMo8Pt4 cuboctahedra, a faceface with one MoPt8 hexagonal bipyramid, and faces with two equivalent MoPt6 octahedra. The corner-sharing octahedra tilt angles range from 58–91°. There are a spread of Pt–Pt bond distances ranging from 2.81–2.86 Å. In the third Pt2- site, Pt2- is bonded to eight Mo2+ and four equivalent Pt2- atoms to form PtMo8Pt4 cuboctahedra that share corners with fourteen PtMo6Pt6 cuboctahedra, corners with eight equivalent MoPt6 octahedra, edges with four equivalent PtMo6Pt6 cuboctahedra, edges with four equivalent MoPt8 hexagonal bipyramids, and faces with twelve PtMo8Pt4 cuboctahedra. The corner-sharing octahedra tilt angles range from 61–119°.

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2020-04-29. Materials Data on MoPt by Materials Project. https://doi.org/10.17188/1745738

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