Materials Data on Mg2Si4O11 by Materials Project
Mg2Si4O11 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a see-saw-like geometry to four O atoms. There is two shorter (1.95 Å) and two longer (1.97 Å) Mg–O bond length. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and an edgeedge with one MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.99–2.12 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the third O site, O is bonded in a bent 120 degrees geometry to two equivalent Mg atoms. In the fourth O site, O is bonded in a linear geometry to two equivalent Si atoms. In the fifth O site, O is bonded in a distorted T-shaped geometry to two Mg and one Si atom. In the sixth O site, O is bonded in a 3-coordinate geometry to two Mg and one Si atom. In the seventh O site, O is bonded in a bent 120 degrees geometry to two Si atoms.