DOE OSTI2020
Li5FeO4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twenty inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two FeO4 tetrahedra, corners with four LiO4 tetrahedra, corners with four LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.96–2.15 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with four FeO4 tetrahedra, corners with five LiO4 tetrahedra, and edges with four LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.98–2.30 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two FeO4 tetrahedra, corners with eight LiO4 tetrahedra, corners with two equivalent LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.93–2.18 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two FeO4 tetrahedra, corners with seven LiO4 tetrahedra, corners with two equivalent LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.87–2.24 Å. In the fifth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with six LiO4 tetrahedra, corners with three LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.97–2.12 Å. In the sixth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with five LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, and edges with four LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.93–2.03 Å. In the seventh Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with four LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and edges with two LiO4 trigonal pyramids. There are a spread of Li–O bond distances ranging from 1.98–2.01 Å. In the eighth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two FeO4 tetrahedra, corners with seven LiO4 tetrahedra, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and edges with two LiO4 trigonal pyramids. There are a spread of Li–O bond distances ranging from 1.91–2.09 Å. In the ninth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with four FeO4 tetrahedra, corners with seven LiO4 tetrahedra, edges with three LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 2.01–2.11 Å. In the tenth 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 1.92–2.31 Å. In the eleventh Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with two FeO4 tetrahedra, corners with six LiO4 tetrahedra, corners with two equivalent LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.97–2.09 Å. In the twelfth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with four FeO4 tetrahedra, corners with eight LiO4 tetrahedra, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.00–2.34 Å. In the thirteenth Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.81–2.46 Å. In the fourteenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with four LiO4 tetrahedra, corners with three LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.92–2.07 Å. In the fifteenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with eight LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.95–2.19 Å. In the sixteenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two FeO4 tetrahedra, corners with nine LiO4 tetrahedra, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.92–2.07 Å. In the seventeenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with five LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one LiO4 tetrahedra, an edgeedge with one FeO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.98–2.07 Å. In the eighteenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with nine LiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, an edgeedge with one FeO4 tetrahedra, edges with two LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.95–2.15 Å. In the nineteenth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with four FeO4 tetrahedra, corners with six LiO4 tetrahedra, corners with two equivalent LiO4 trigonal pyramids, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.01–2.20 Å. In the twentieth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two FeO4 tetrahedra, corners with three LiO4 tetrahedra, corners with two equivalent LiO4 trigonal pyramids, an edgeedge with one FeO4 tetrahedra, edges with four LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.91–2.00 Å. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with seven LiO4 tetrahedra, corners with three LiO4 trigonal pyramids, and edges with four LiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.89–1.93 Å. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with five LiO4 tetrahedra, corners with three LiO4 trigonal pyramids, edges with three LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There is one shorter (1.85 Å) and three longer (1.92 Å) Fe–O bond length. In the third Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with ten LiO4 tetrahedra, corners with three LiO4 trigonal pyramids, and edges with four LiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.91–1.95 Å. In the fourth Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with eight LiO4 tetrahedra, corners with five LiO4 trigonal pyramids, and edges with two LiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.89–1.97 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Fe3+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Fe3+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Fe3+ atom. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to four Li1+ and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Fe3+ atom. In the seventh O2- site, O2- is bonded to five Li1+ and one Fe3+ atom to form distorted OLi5Fe octahedra that share a cornercorner with one OLi5Fe octahedra, corners with two OLi4Fe trigonal bipyramids, an edgeedge with one OLi5Fe octahedra, and an edgeedge with one OLi5Fe pentagonal pyramid. The corner-sharing octahedral tilt angles are 49°. In the eighth O2- site, O2- is bonded to five Li1+ and one Fe3+ atom to form distorted OLi5Fe octahedra that share a cornercorner with one OLi5Fe octahedra, corners with two OLi4Fe trigonal bipyramids, and an edgeedge with one OLi5Fe octahedra. The corner-sharing octahedral tilt angles are 49°. In the ninth O2- site, O2- is bonded in a 7-coordinate geometry to six Li1+ and one Fe3+ atom. In the tenth O2- site, O2- is bonded to five Li1+ and one Fe3+ atom to form a mixture of distorted edge and corner-sharing OLi5Fe pentagonal pyramids. The corner-sharing octahedral tilt angles are 50°. In the eleventh O2- site, O2- is bonded to four Li1+ and one Fe3+ atom to form distorted OLi4Fe trigonal bipyramids that share corners with four OLi5Fe octahedra and corners with two equivalent OLi4Fe trigonal bipyramids. The corner-sharing octahedra tilt angles range from 60–70°. In the twelfth O2- site, O2- is bonded to four Li1+ and one Fe3+ atom to form distorted OLi4Fe trigonal bipyramids that share corners with two OLi5Fe octahedra, corners with two equivalent OLi4Fe trigonal bipyramids, and edges with two OLi5Fe octahedra. The corner-sharing octahedra tilt angles range from 46–50°. In the thirteenth O2- site, O2- is bonded to five Li1+ and one Fe3+ atom to form distorted OLi5Fe octahedra that share a cornercorner with one OLi5Fe octahedra, a cornercorner with one OLi4Fe trigonal bipyramid, an edgeedge with one OLi5Fe octahedra, and an edgeedge with one OLi4Fe trigonal bipyramid. The corner-sharing octahedral tilt angles are 42°. In the fourteenth O2- site, O2- is bonded to five Li1+ and one Fe3+ atom to form distorted OLi5Fe octahedra that share a cornercorner with one OLi5Fe octahedra, a cornercorner with one OLi5Fe pentagonal pyramid, a cornercorner with one OLi4Fe trigonal bipyramid, an edgeedge with one OLi5Fe octahedra, and an edgeedge with one OLi4Fe trigonal bipyramid. The corner-sharing octahedral tilt angles are 42°. In the fifteenth O2- site, O2- is bonded in a 7-coordinate geometry to six Li1+ and one Fe3+ atom. In the sixteenth O2- site, O2- is bonded in a 7-coordinate geometry to six Li1+ and one Fe3+ atom.