Materials Data on Sm3SbO7 by Materials Project

Abstract

Sm3SbO7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Sm3+ sites. In the first Sm3+ site, Sm3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Sm–O bond distances ranging from 2.38–2.70 Å. In the second Sm3+ site, Sm3+ is bonded to seven O2- atoms to form distorted SmO7 pentagonal bipyramids that share corners with two equivalent SbO6 octahedra, a cornercorner with one SmO7 pentagonal bipyramid, edges with two equivalent SbO6 octahedra, and edges with three equivalent SmO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. There are a spread of Sm–O bond distances ranging from 2.28–2.55 Å. Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with two equivalent SbO6 octahedra, corners with four equivalent SmO7 pentagonal bipyramids, and edges with four equivalent SmO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 40°. There are four shorter (2.00 Å) and two longer (2.05 Å) Sb–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Sm3+ and one Sb5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sm3+ and two equivalent Sb5+ atoms. In the third O2- site, O2- is bonded to four Sm3+ atoms to form a mixture of edge and corner-sharing OSm4 tetrahedra. In the fourth O2- site, O2- is bonded to four Sm3+ atoms to form a mixture of edge and corner-sharing OSm4 tetrahedra.