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DOE OSTI · 1297573

Materials Data on Li7Ti7Nb5O30 by Materials Project

Abstract

Li7Ti7Nb5O30 is Ilmenite-derived structured and crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are seven inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.01 Å) and three longer (2.43 Å) Li–O bond lengths. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.13 Å) and three longer (2.24 Å) Li–O bond lengths. In the third Li1+ site, Li1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are three shorter (1.96 Å) and three longer (2.47 Å) Li–O bond lengths. In the fourth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.10 Å) and three longer (2.40 Å) Li–O bond lengths. In the fifth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.05 Å) and three longer (2.39 Å) Li–O bond lengths. In the sixth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are three shorter (2.00 Å) and three longer (2.42 Å) Li–O bond lengths. In the seventh Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 octahedra that share edges with three equivalent NbO6 octahedra, a faceface with one TiO6 octahedra, and a faceface with one NbO6 octahedra. There are three shorter (1.99 Å) and three longer (2.03 Å) Li–O bond lengths. There are seven inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with three equivalent NbO6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are three shorter (1.86 Å) and three longer (2.14 Å) Ti–O bond lengths. In the second Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (1.88 Å) and three longer (2.14 Å) Ti–O bond lengths. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent TiO6 octahedra, corners with three equivalent NbO6 octahedra, and edges with three equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–46°. There are three shorter (1.89 Å) and three longer (2.14 Å) Ti–O bond lengths. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with three equivalent TiO6 octahedra, corners with three equivalent NbO6 octahedra, and a faceface with one TiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–42°. There are three shorter (1.87 Å) and three longer (2.15 Å) Ti–O bond lengths. In the fifth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with three equivalent NbO6 octahedra, edges with three equivalent TiO6 octahedra, and a faceface with one TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are three shorter (1.90 Å) and three longer (2.10 Å) Ti–O bond lengths. In the sixth Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (1.88 Å) and three longer (2.14 Å) Ti–O bond lengths. In the seventh Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent NbO6 octahedra and a faceface with one LiO6 octahedra. The corner-sharing octahedral tilt angles are 28°. There is three shorter (1.88 Å) and three longer (2.11 Å) Ti–O bond length. There are five inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 32–41°. There are three shorter (1.96 Å) and three longer (2.04 Å) Nb–O bond lengths. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three equivalent TiO6 octahedra, corners with three equivalent NbO6 octahedra, and edges with three equivalent LiO6 octahedra. The corner-sharing octahedra tilt angles range from 28–37°. All Nb–O bond lengths are 2.03 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three equivalent TiO6 octahedra and corners with three equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 32–42°. There are three shorter (1.97 Å) and three longer (2.04 Å) Nb–O bond lengths. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with nine TiO6 octahedra. The corner-sharing octahedra tilt angles range from 35–53°. There are three shorter (1.93 Å) and three longer (2.14 Å) Nb–O bond lengths. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and a faceface with one LiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–41°. There are three shorter (1.97 Å) and three longer (2.08 Å) Nb–O bond lengths. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted square co-planar geometry to two Li1+, one Ti4+, and one Nb5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ti4+ and one Nb5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted see-saw-like geometry to one Li1+ and three Ti4+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Ti4+, and one Nb5+ atom. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to one Li1+ and three Ti4+ atoms. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Ti4+, and one Nb5+ atom. In the ninth O2- site, O2- is bonded in a distorted see-saw-like geometry to one Li1+ and three Ti4+ atoms. In the tenth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted corner and edge-sharing OLi2Nb2 tetrahedra.

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2020-07-14. Materials Data on Li7Ti7Nb5O30 by Materials Project. https://doi.org/10.17188/1297573

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