Materials Data on La2Sn2O7 by Materials Project

Abstract

La2Sn2O7 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. La3+ is bonded to eight O2- atoms to form distorted LaO8 hexagonal bipyramids that share edges with six equivalent LaO8 hexagonal bipyramids and edges with six equivalent SnO6 octahedra. There are two shorter (2.34 Å) and six longer (2.64 Å) La–O bond lengths. Sn4+ is bonded to six equivalent O2- atoms to form SnO6 octahedra that share corners with six equivalent SnO6 octahedra and edges with six equivalent LaO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 50°. All Sn–O bond lengths are 2.11 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent La3+ atoms to form OLa4 tetrahedra that share corners with sixteen OLa4 tetrahedra and edges with six equivalent OLa2Sn2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent La3+ and two equivalent Sn4+ atoms to form a mixture of distorted edge and corner-sharing OLa2Sn2 tetrahedra.