Materials Data on Li2FeSi3O8 by Materials Project
Li2FeSi3O8 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra and corners with six SiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.89–2.22 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra and corners with six SiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.90–2.51 Å. Fe2+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four LiO4 tetrahedra and corners with four SiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.02 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four LiO4 tetrahedra and corners with four SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.65–1.68 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with two equivalent SiO4 tetrahedra, and corners with four LiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.70 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent FeO4 tetrahedra, corners with two equivalent SiO4 tetrahedra, and corners with four LiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.72 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Li1+, one Fe2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Fe2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to one Li1+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Li1+, one Fe2+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to one Li1+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Fe2+, and one Si4+ atom.