Materials Data on Li8Fe7O15 by Materials Project

Abstract

Li8Fe7O15 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent Li sites. In the first Li site, Li is bonded to six O atoms to form LiO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four LiO6 octahedra, edges with five LiO6 octahedra, and edges with seven FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of Li–O bond distances ranging from 1.95–2.24 Å. In the second Li site, Li is bonded to six O atoms to form LiO6 octahedra that share corners with six LiO6 octahedra, edges with four LiO6 octahedra, and edges with eight FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Li–O bond distances ranging from 1.98–2.13 Å. In the third Li site, Li is bonded to six O atoms to form LiO6 octahedra that share corners with six LiO6 octahedra, edges with four LiO6 octahedra, and edges with eight FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Li–O bond distances ranging from 1.98–2.14 Å. In the fourth Li site, Li is bonded to six O atoms to form LiO6 octahedra that share corners with three LiO6 octahedra, corners with three FeO6 octahedra, edges with five FeO6 octahedra, and edges with seven LiO6 octahedra. The corner-sharing octahedra tilt angles range from 1–9°. There are a spread of Li–O bond distances ranging from 1.99–2.20 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six FeO6 octahedra, edges with four FeO6 octahedra, and edges with eight LiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Fe–O bond distances ranging from 1.96–2.13 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with three LiO6 octahedra, corners with three FeO6 octahedra, edges with five FeO6 octahedra, and edges with seven LiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–9°. There are a spread of Fe–O bond distances ranging from 1.90–2.17 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with two equivalent LiO6 octahedra, corners with four FeO6 octahedra, edges with three FeO6 octahedra, and edges with nine LiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–7°. There are a spread of Fe–O bond distances ranging from 1.97–2.22 Å. In the fourth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six FeO6 octahedra, edges with four FeO6 octahedra, and edges with eight LiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.02 Å) and four longer (2.10 Å) Fe–O bond lengths. There are eight inequivalent O sites. In the first O site, O is bonded to two equivalent Li and four equivalent Fe atoms to form OLi2Fe4 octahedra that share corners with six OLi2Fe4 octahedra and edges with twelve OLi4Fe2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O is bonded to four Li and two Fe atoms to form OLi4Fe2 octahedra that share corners with six OLi4Fe2 octahedra and edges with twelve OLi2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the third O site, O is bonded to two Li and four Fe atoms to form OLi2Fe4 octahedra that share corners with six OLi2Fe4 octahedra and edges with twelve OLi4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. In the fourth O site, O is bonded to four Li and two equivalent Fe atoms to form a mixture of edge and corner-sharing OLi4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 2–10°. In the fifth O site, O is bonded to four Li and two Fe atoms to form OLi4Fe2 octahedra that share corners with six OLi4Fe2 octahedra and edges with twelve OLi2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the sixth O site, O is bonded to four Li and two Fe atoms to form OLi4Fe2 octahedra that share corners with six OLi4Fe2 octahedra and edges with twelve OLi2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the seventh O site, O is bonded to two Li and four Fe atoms to form a mixture of edge and corner-sharing OLi2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 1–9°. In the eighth O site, O is bonded to three Li and three equivalent Fe atoms to form a mixture of edge and corner-sharing OLi3Fe3 octahedra. The corner-sharing octahedra tilt angles range from 1–10°.