Materials Data on Pr2FeSbO7 by Materials Project
Pr2(FeSb)O7 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are two inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to eight O2- atoms to form distorted PrO8 hexagonal bipyramids that share edges with two equivalent PrO8 hexagonal bipyramids, edges with two equivalent FeO6 octahedra, and edges with four equivalent SbO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.28–2.62 Å. In the second Pr3+ site, Pr3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.31–2.62 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent SbO6 octahedra, and edges with two equivalent PrO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 48–50°. There are two shorter (2.06 Å) and four longer (2.10 Å) Fe–O bond lengths. Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with two equivalent SbO6 octahedra, corners with four equivalent FeO6 octahedra, and edges with four equivalent PrO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–48°. There are four shorter (2.01 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 to two equivalent Pr3+ and two equivalent Fe3+ atoms to form distorted OPr2Fe2 tetrahedra that share corners with six OPr2Fe2 tetrahedra and an edgeedge with one OPr4 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Pr3+ and two equivalent Sb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Pr3+, one Fe3+, and one Sb5+ atom. In the fourth O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra.