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DOE OSTI · 1307613

Materials Data on Li8La4TiNb7O28 by Materials Project

Abstract

Li8La4TiNb7O28 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to five O2- atoms to form LiO5 trigonal bipyramids that share a cornercorner with one TiO6 octahedra, a cornercorner with one NbO6 octahedra, corners with four equivalent LiO5 trigonal bipyramids, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 59–62°. There are a spread of Li–O bond distances ranging from 2.01–2.22 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.06–2.75 Å. In the third Li1+ site, Li1+ is bonded to five O2- atoms to form LiO5 trigonal bipyramids that share corners with two NbO6 octahedra, corners with four equivalent LiO5 trigonal bipyramids, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedral tilt angles are 60°. There are a spread of Li–O bond distances ranging from 2.00–2.22 Å. In the fourth 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 2.09–2.11 Å. In the fifth Li1+ site, Li1+ is bonded to five O2- atoms to form LiO5 trigonal bipyramids that share corners with two equivalent NbO6 octahedra, corners with four equivalent LiO5 trigonal bipyramids, an edgeedge with one TiO6 octahedra, and an edgeedge with one NbO6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Li–O bond distances ranging from 2.03–2.25 Å. In the sixth Li1+ site, Li1+ is bonded to five O2- atoms to form LiO5 trigonal bipyramids that share corners with two equivalent NbO6 octahedra, corners with four equivalent LiO5 trigonal bipyramids, and edges with two NbO6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Li–O bond distances ranging from 2.01–2.23 Å. There are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.50–2.93 Å. In the second La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.49–2.82 Å. In the third La3+ site, La3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.50–2.93 Å. Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with five NbO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 2–32°. There are a spread of Ti–O bond distances ranging from 1.82–2.18 Å. There are five inequivalent Nb+4.57+ sites. In the first Nb+4.57+ site, Nb+4.57+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with four equivalent NbO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 7–32°. There are a spread of Nb–O bond distances ranging from 1.91–2.13 Å. In the second Nb+4.57+ site, Nb+4.57+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with five NbO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 4–35°. There are a spread of Nb–O bond distances ranging from 1.88–2.18 Å. In the third Nb+4.57+ site, Nb+4.57+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 5–34°. There are a spread of Nb–O bond distances ranging from 1.89–2.17 Å. In the fourth Nb+4.57+ site, Nb+4.57+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with four equivalent TiO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 2–32°. There are a spread of Nb–O bond distances ranging from 1.89–2.18 Å. In the fifth Nb+4.57+ site, Nb+4.57+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with five NbO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 7–32°. There are a spread of Nb–O bond distances ranging from 1.90–2.16 Å. There are twenty-one inequivalent O2- sites. In the first O2- site, O2- is bonded in a T-shaped geometry to one Li1+, two La3+, and two equivalent Nb+4.57+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two equivalent Nb+4.57+ atoms. In the third O2- site, O2- is bonded to two equivalent La3+, one Ti4+, and one Nb+4.57+ atom to form distorted corner-sharing OLa2TiNb tetrahedra. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, two equivalent La3+, one Ti4+, and one Nb+4.57+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent La3+ and two Nb+4.57+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two Nb+4.57+ atoms. In the seventh O2- site, O2- is bonded in a T-shaped geometry to one Li1+, two La3+, and two equivalent Nb+4.57+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two equivalent Nb+4.57+ atoms. In the ninth O2- site, O2- is bonded to two La3+ and two Nb+4.57+ atoms to form distorted OLa2Nb2 trigonal pyramids that share corners with six OLa2Nb2 tetrahedra, corners with two OLi4Nb trigonal bipyramids, and an edgeedge with one OLa2Nb2 trigonal pyramid. In the tenth O2- site, O2- is bonded to four Li1+ and one Ti4+ atom to form distorted OLi4Ti trigonal bipyramids that share a cornercorner with one OLa2TiNb tetrahedra, corners with four equivalent OLi4Nb trigonal bipyramids, and edges with four equivalent OLi4Nb trigonal bipyramids. In the eleventh O2- site, O2- is bonded to four Li1+ and one Nb+4.57+ atom to form a mixture of distorted edge and corner-sharing OLi4Nb trigonal bipyramids. In the twelfth O2- site, O2- is bonded to four Li1+ and one Nb+4.57+ atom to form distorted OLi4Nb trigonal bipyramids that share a cornercorner with one OLa2Nb2 tetrahedra, corners with four equivalent OLi4Nb trigonal bipyramids, a cornercorner with one OLa2Nb2 trigonal pyramid, and edges with four OLi4Ti trigonal bipyramids. In the thirteenth O2- site, O2- is bonded to four Li1+ and one Nb+4.57+ atom to form distorted OLi4Nb trigonal bipyramids that share a cornercorner with one OLa2Nb2 tetrahedra, corners with four equivalent OLi4Nb trigonal bipyramids, a cornercorner with one OLa2Nb2 trigonal pyramid, and edges with four OLi4Nb trigonal bipyramids. In the fourteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent La3+, one Ti4+, and one Nb+4.57+ atom. In the fifteenth O2- site, O2- is bonded to two La3+ and two equivalent Nb+4.57+ atoms to form distorted OLa2Nb2 tetrahedra that share corners with two equivalent OLi4Nb trigonal bipyramids, corners with six equivalent OLa2Nb2 trigonal pyramids, and an edgeedge with one OLa2Nb2 tetrahedra. In the sixteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, two equivalent La3+, one Ti4+, and one Nb+4.57+ atom. In the seventeenth O2- site, O2- is bonded to two La3+ and two equivalent Nb+4.57+ atoms to form distorted OLa2Nb2 tetrahedra that share corners with two equivalent OLi4Nb trigonal bipyramids, corners with six equivalent OLa2Nb2 trigonal pyramids, and an edgeedge with one OLa2Nb2 tetrahedra. In the eighteenth O2- site, O2- is bonded in a T-shaped geometry to one Li1+ and two Nb+4.57+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent La3+ and two Nb+4.57+ atoms. In the twentieth O2- site, O2- is bonded to four Li1+ and one Nb+4.57+ atom to form distorted OLi4Nb trigonal bipyramids that share a cornercorner with one OLa2TiNb tetrahedra, corners with four equivalent OLi4Ti trigonal bipyramids, and edges with four equivalent OLi4Nb trigonal bipyramids. In the twenty-first O2- site, O2- is bonded to four Li1+ and one Nb+4.57+ atom to form a mixture of distorted edge and corner-sharing OLi4Nb trigonal bipyramids.

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2020-07-15. Materials Data on Li8La4TiNb7O28 by Materials Project. https://doi.org/10.17188/1307613

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