DOI: 10.17188/1272014
title: Materials Data on Li2Mg2Si4O11 by Materials Project

description: Li2Mg2Si4O11 is Esseneite-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first 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 2.05–2.23 Å. In the second Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.29 Å. There are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with four MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.30 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with four MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.46 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 2–57°. There are a spread of Si–O bond distances ranging from 1.60–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–65°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–65°. There are a spread of Si–O bond distances ranging from 1.62–1.68 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a see-saw-like geometry to two Li1+, one Mg2+, and one Si4+ atom. In the second O2- site, O2- is bonded to two Li1+, one Mg2+, and one Si4+ atom to form distorted OLi2MgSi trigonal pyramids that share a cornercorner with one OMg3Si tetrahedra and edges with two OLiMg2Si trigonal pyramids. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the sixth O2- site, O2- is bonded to three Mg2+ and one Si4+ atom to form distorted OMg3Si tetrahedra that share corners with five OLi2MgSi trigonal pyramids, an edgeedge with one OMg3Si tetrahedra, and an edgeedge with one OLiMg2Si trigonal pyramid. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Si4+ atoms. In the ninth O2- site, O2- is bonded to one Li1+, two Mg2+, and one Si4+ atom to form distorted OLiMg2Si trigonal pyramids that share corners with three equivalent OMg3Si tetrahedra, corners with three equivalent OLiMg2Si trigonal pyramids, and an edgeedge with one OLi2MgSi trigonal pyramid. In the tenth O2- site, O2- is bonded to one Li1+, two Mg2+, and one Si4+ atom to form distorted OLiMg2Si trigonal pyramids that share a cornercorner with one OMg3Si tetrahedra, corners with three equivalent OLiMg2Si trigonal pyramids, an edgeedge with one OMg3Si tetrahedra, and an edgeedge with one OLi2MgSi trigonal pyramid. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and two Si4+ atoms.