DOI: 10.17188/1701539
title: Materials Data on Ca2Pr4(Mo2O7)3 by Materials Project

description: Ca2Pr4(Mo2O7)3 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. Ca2+ is bonded to eight O2- atoms to form distorted CaO8 hexagonal bipyramids that share an edgeedge with one CaO8 hexagonal bipyramid, edges with five PrO8 hexagonal bipyramids, and edges with six MoO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.25–2.69 Å. 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 three equivalent CaO8 hexagonal bipyramids, edges with three PrO8 hexagonal bipyramids, and edges with six MoO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.30–2.65 Å. In the second Pr3+ site, Pr3+ is bonded to eight O2- atoms to form distorted PrO8 hexagonal bipyramids that share edges with two equivalent CaO8 hexagonal bipyramids, edges with four PrO8 hexagonal bipyramids, and edges with six MoO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.31–2.68 Å. There are three inequivalent Mo+4.33+ sites. In the first Mo+4.33+ site, Mo+4.33+ is bonded to six O2- atoms to form MoO6 octahedra that share corners with six MoO6 octahedra, an edgeedge with one CaO8 hexagonal bipyramid, and edges with five PrO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 47–51°. There are a spread of Mo–O bond distances ranging from 1.99–2.09 Å. In the second Mo+4.33+ site, Mo+4.33+ is bonded to six O2- atoms to form MoO6 octahedra that share corners with six MoO6 octahedra, edges with three equivalent CaO8 hexagonal bipyramids, and edges with three PrO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–51°. There are a spread of Mo–O bond distances ranging from 2.02–2.12 Å. In the third Mo+4.33+ site, Mo+4.33+ is bonded to six O2- atoms to form MoO6 octahedra that share corners with six MoO6 octahedra, edges with two equivalent CaO8 hexagonal bipyramids, and edges with four PrO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–48°. There are two shorter (2.03 Å) and four longer (2.04 Å) Mo–O bond lengths. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Pr3+ atoms to form OCa2Pr2 tetrahedra that share corners with four equivalent OCaPr3 tetrahedra and an edgeedge with one OCa2Mo2 tetrahedra. In the second O2- site, O2- is bonded to one Ca2+ and three Pr3+ atoms to form OCaPr3 tetrahedra that share corners with seven OCa2Pr2 tetrahedra and an edgeedge with one OPr2Mo2 tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Pr3+, and two Mo+4.33+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Pr3+, and two equivalent Mo+4.33+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Pr3+ and two Mo+4.33+ atoms to form a mixture of distorted edge and corner-sharing OPr2Mo2 tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Pr3+, and two Mo+4.33+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Pr3+ and two equivalent Mo+4.33+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Pr3+ and two Mo+4.33+ atoms. In the ninth O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Mo+4.33+ atoms to form distorted OCa2Mo2 tetrahedra that share corners with four OCaPr3 tetrahedra and an edgeedge with one OCa2Pr2 tetrahedra. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Pr3+ and two Mo+4.33+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Pr3+, and two Mo+4.33+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Pr3+, and two Mo+4.33+ atoms.