Materials Data on In2Si2O7 by Materials Project
In2Si2O7 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. In3+ is bonded to eight O2- atoms to form distorted InO8 hexagonal bipyramids that share edges with six equivalent InO8 hexagonal bipyramids and edges with six equivalent SiO6 octahedra. There are two shorter (2.07 Å) and six longer (2.40 Å) In–O bond lengths. Si4+ is bonded to six equivalent O2- atoms to form SiO6 octahedra that share corners with six equivalent SiO6 octahedra and edges with six equivalent InO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 44°. All Si–O bond lengths are 1.82 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent In3+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded to four equivalent In3+ atoms to form corner-sharing OIn4 tetrahedra.