MgPr(BiO3)2 crystallizes in the orthorhombic Pmn2_1 space group. Mg(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form distorted MgO4 tetrahedra that share corners with eight equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 65-83°. Pr(1) is bonded in a 8-coordinate geometry to one O(1), one O(4), two equivalent O(2), and four equivalent O(3) atoms. Bi(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share corners with six equivalent Bi(1)O6 octahedra and corners with four equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Pr(1), and two equivalent Bi(1) atoms to form distorted corner-sharing OPrMgBi2 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Pr(1) and two equivalent Bi(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Pr(1), and two equivalent Bi(1) atoms. In the fourth O site, O(4) is bonded to one Mg(1), one Pr(1), and two equivalent Bi(1) atoms to form distorted corner-sharing OPrMgBi2 tetrahedra.
MgPr(BiO3)2 crystallizes in the orthorhombic Pmn2_1 space group. Mg(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form distorted MgO4 tetrahedra that share corners with eight equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 65-83°. The Mg(1)-O(1) bond length is 2.51 Å. The Mg(1)-O(4) bond length is 2.00 Å. Both Mg(1)-O(3) bond lengths are 2.09 Å. Pr(1) is bonded in a 8-coordinate geometry to one O(1), one O(4), two equivalent O(2), and four equivalent O(3) atoms. The Pr(1)-O(1) bond length is 2.41 Å. The Pr(1)-O(4) bond length is 2.40 Å. Both Pr(1)-O(2) bond lengths are 2.32 Å. There are two shorter (2.83 Å) and two longer (3.10 Å) Pr(1)-O(3) bond lengths. Bi(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share corners with six equivalent Bi(1)O6 octahedra and corners with four equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. The Bi(1)-O(1) bond length is 2.34 Å. The Bi(1)-O(4) bond length is 2.40 Å. There is one shorter (2.22 Å) and one longer (2.26 Å) Bi(1)-O(2) bond length. There is one shorter (2.32 Å) and one longer (2.40 Å) Bi(1)-O(3) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Pr(1), and two equivalent Bi(1) atoms to form distorted corner-sharing OPrMgBi2 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Pr(1) and two equivalent Bi(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Pr(1), and two equivalent Bi(1) atoms. In the fourth O site, O(4) is bonded to one Mg(1), one Pr(1), and two equivalent Bi(1) atoms to form distorted corner-sharing OPrMgBi2 tetrahedra.