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DOE OSTI · 1262469

Materials Data on Si2P2Pt by Materials Project

Abstract

PtSi2P2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded to three Si4- and three P5+ atoms to form PtSi3P3 octahedra that share corners with three PtSi3P3 octahedra, corners with six SiSiP2Pt tetrahedra, and edges with two PtSi3P3 octahedra. The corner-sharing octahedra tilt angles range from 58–62°. There are a spread of Pt–Si bond distances ranging from 2.42–2.49 Å. There are two shorter (2.40 Å) and one longer (2.44 Å) Pt–P bond lengths. In the second Pt2- site, Pt2- is bonded to three Si4- and three P5+ atoms to form PtSi3P3 octahedra that share corners with three PtSi3P3 octahedra, a cornercorner with one PSi3Pt tetrahedra, corners with five SiSi2PPt tetrahedra, and an edgeedge with one PtSi3P3 octahedra. The corner-sharing octahedra tilt angles range from 58–65°. There are a spread of Pt–Si bond distances ranging from 2.43–2.49 Å. There are a spread of Pt–P bond distances ranging from 2.41–2.50 Å. In the third Pt2- site, Pt2- is bonded to three Si4- and three P5+ atoms to form PtSi3P3 octahedra that share corners with three PtSi3P3 octahedra, a cornercorner with one PSi3Pt tetrahedra, corners with nine SiSiPPt2 tetrahedra, and an edgeedge with one PtSi3P3 octahedra. The corner-sharing octahedra tilt angles range from 53–61°. There are a spread of Pt–Si bond distances ranging from 2.41–2.46 Å. There are a spread of Pt–P bond distances ranging from 2.42–2.49 Å. In the fourth Pt2- site, Pt2- is bonded to three Si4- and three P5+ atoms to form PtSi3P3 octahedra that share corners with three PtSi3P3 octahedra, corners with two equivalent PSi3Pt tetrahedra, corners with five SiSiPt3 tetrahedra, and edges with two PtSi3P3 octahedra. The corner-sharing octahedra tilt angles range from 53–65°. There are a spread of Pt–Si bond distances ranging from 2.41–2.46 Å. There are one shorter (2.42 Å) and two longer (2.45 Å) Pt–P bond lengths. There are eight inequivalent Si4- sites. In the first Si4- site, Si4- is bonded to three Pt2- and one Si4- atom to form distorted SiSiPt3 tetrahedra that share a cornercorner with one PtSi3P3 octahedra, corners with two equivalent PSi3Pt tetrahedra, and corners with six SiSiPPt2 tetrahedra. The corner-sharing octahedral tilt angles are 69°. The Si–Si bond length is 2.34 Å. In the second Si4- site, Si4- is bonded to two Pt2-, one Si4-, and one P5+ atom to form distorted SiSiPPt2 tetrahedra that share a cornercorner with one PtSi3P3 octahedra, a cornercorner with one PSi3Pt tetrahedra, and corners with eight SiSiPt3 tetrahedra. The corner-sharing octahedral tilt angles are 68°. The Si–Si bond length is 2.32 Å. The Si–P bond length is 2.30 Å. In the third Si4- site, Si4- is bonded to two Pt2- and two Si4- atoms to form distorted SiSi2Pt2 tetrahedra that share a cornercorner with one PtSi3P3 octahedra, corners with five SiSiPt3 tetrahedra, and an edgeedge with one SiSi2Pt2 tetrahedra. The corner-sharing octahedral tilt angles are 69°. There are one shorter (2.31 Å) and one longer (2.35 Å) Si–Si bond lengths. In the fourth Si4- site, Si4- is bonded to one Pt2-, one Si4-, and two P5+ atoms to form distorted SiSiP2Pt tetrahedra that share corners with four PtSi3P3 octahedra and corners with four SiSiPt3 tetrahedra. The corner-sharing octahedra tilt angles range from 68–81°. There are one shorter (2.28 Å) and one longer (2.29 Å) Si–P bond lengths. In the fifth Si4- site, Si4- is bonded to two Pt2- and two Si4- atoms to form distorted SiSi2Pt2 tetrahedra that share a cornercorner with one PtSi3P3 octahedra, corners with five SiSiPt3 tetrahedra, and an edgeedge with one SiSi2Pt2 tetrahedra. The corner-sharing octahedral tilt angles are 63°. There are one shorter (2.30 Å) and one longer (2.32 Å) Si–Si bond lengths. In the sixth Si4- site, Si4- is bonded to one Pt2-, two Si4-, and one P5+ atom to form distorted SiSi2PPt tetrahedra that share corners with five PtSi3P3 octahedra, a cornercorner with one PSi3Pt tetrahedra, and corners with four SiSiPt3 tetrahedra. The corner-sharing octahedra tilt angles range from 47–70°. The Si–P bond length is 2.32 Å. In the seventh Si4- site, Si4- is bonded to three Si4- and one P5+ atom to form distorted SiSi3P tetrahedra that share corners with seven PtSi3P3 octahedra, a cornercorner with one PSi3Pt tetrahedra, and corners with two equivalent SiSi2PPt tetrahedra. The corner-sharing octahedra tilt angles range from 53–77°. The Si–P bond length is 2.26 Å. In the eighth Si4- site, Si4- is bonded to one Pt2- and three P5+ atoms to form SiP3Pt tetrahedra that share corners with five PtSi3P3 octahedra and corners with four SiSiPPt2 tetrahedra. The corner-sharing octahedra tilt angles range from 48–69°. There are two shorter (2.28 Å) and one longer (2.29 Å) Si–P bond lengths. There are eight inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a single-bond geometry to one Si4- atom. In the second P5+ site, P5+ is bonded in a distorted trigonal non-coplanar geometry to two Pt2- and one Si4- atom. In the third P5+ site, P5+ is bonded in a distorted bent 120 degrees geometry to one Pt2- and one Si4- atom. In the fourth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Pt2- atoms. In the fifth P5+ site, P5+ is bonded in a bent 120 degrees geometry to two Pt2- atoms. In the sixth P5+ site, P5+ is bonded in a bent 120 degrees geometry to one Pt2- and one Si4- atom. In the seventh P5+ site, P5+ is bonded to one Pt2- and three Si4- atoms to form PSi3Pt tetrahedra that share corners with four PtSi3P3 octahedra and corners with five SiSiPt3 tetrahedra. The corner-sharing octahedra tilt angles range from 52–72°. In the eighth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to two Pt2- and one Si4- atom.

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2020-05-02. Materials Data on Si2P2Pt by Materials Project. https://doi.org/10.17188/1262469

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