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DOE OSTI · 1700732

Materials Data on NaLi5Fe2P2(CO7)2 by Materials Project

Abstract

NaLi5Fe2P2(CO7)2 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.91 Å. There are five inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.94–2.22 Å. In the second Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with two FeO6 octahedra, corners with three PO4 tetrahedra, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 64–89°. There are a spread of Li–O bond distances ranging from 2.03–2.48 Å. In the third Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with two FeO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and edges with two equivalent LiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 69–87°. There are a spread of Li–O bond distances ranging from 2.07–2.49 Å. In the fourth Li1+ site, Li1+ is bonded to five O2- atoms to form LiO5 trigonal bipyramids that share corners with two FeO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and edges with two equivalent LiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 69–85°. There are a spread of Li–O bond distances ranging from 2.11–2.30 Å. In the fifth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 1.94–2.61 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with four PO4 tetrahedra, corners with three LiO5 trigonal bipyramids, and an edgeedge with one LiO5 trigonal bipyramid. There are a spread of Fe–O bond distances ranging from 2.07–2.38 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with four PO4 tetrahedra, corners with three LiO5 trigonal bipyramids, and edges with two LiO5 trigonal bipyramids. There are a spread of Fe–O bond distances ranging from 2.07–2.32 Å. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.29 Å) and two longer (1.30 Å) C–O bond length. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.29–1.31 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and corners with four LiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 42–60°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and corners with five LiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 42–61°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+, two Li1+, and one C4+ atom to form distorted edge-sharing ONaLi2C tetrahedra. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+, one Li1+, one Fe2+, and one C4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Li1+, one Fe2+, and one C4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Li1+, one Fe2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Li1+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded to one Na1+, one Li1+, one Fe2+, and one P5+ atom to form distorted edge-sharing ONaLiFeP tetrahedra. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Li1+, one Fe2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Fe2+, and one P5+ atom. In the ninth O2- site, O2- is bonded to two Li1+, one Fe2+, and one P5+ atom to form distorted edge-sharing OLi2FeP tetrahedra. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Fe2+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Fe2+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to two Li1+, one Fe2+, and one C4+ atom. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Fe2+, and one C4+ atom. In the fourteenth O2- site, O2- is bonded to three Li1+ and one C4+ atom to form edge-sharing OLi3C tetrahedra.

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2020-04-30. Materials Data on NaLi5Fe2P2(CO7)2 by Materials Project. https://doi.org/10.17188/1700732

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