Pr2ScNbO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms to form distorted PrO8 hexagonal bipyramids that share edges with two equivalent Pr(1)O8 hexagonal bipyramids, edges with two equivalent Sc(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. In the second Pr site, Pr(2) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms. Sc(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form ScO6 octahedra that share corners with two equivalent Sc(1)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and edges with two equivalent Pr(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 49-55°. Nb(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Sc(1)O6 octahedra, and edges with four equivalent Pr(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-49°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Pr(1) and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded to two equivalent Pr(2) and two equivalent Sc(1) atoms to form distorted OPr2Sc2 tetrahedra that share corners with two equivalent O(4)Pr4 tetrahedra, corners with four equivalent O(2)Pr2Sc2 tetrahedra, corners with eight equivalent O(3)Pr2ScNb tetrahedra,  an edgeedge with one O(4)Pr4 tetrahedra, and edges with four equivalent O(3)Pr2ScNb tetrahedra. In the third O site, O(3) is bonded to one Pr(1), one Pr(2), one Sc(1), and one Nb(1) atom to form distorted OPr2ScNb tetrahedra that share corners with two equivalent O(2)Pr2Sc2 tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra, corners with eight equivalent O(3)Pr2ScNb tetrahedra,  an edgeedge with one O(2)Pr2Sc2 tetrahedra,  an edgeedge with one O(4)Pr4 tetrahedra, and edges with two equivalent O(3)Pr2ScNb tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Pr(1) and two equivalent Pr(2) atoms to form OPr4 tetrahedra that share corners with two equivalent O(2)Pr2Sc2 tetrahedra, corners with four equivalent O(4)Pr4 tetrahedra, corners with eight equivalent O(3)Pr2ScNb tetrahedra,  an edgeedge with one O(2)Pr2Sc2 tetrahedra, and edges with four equivalent O(3)Pr2ScNb tetrahedra.
Pr2ScNbO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms to form distorted PrO8 hexagonal bipyramids that share edges with two equivalent Pr(1)O8 hexagonal bipyramids, edges with two equivalent Sc(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. Both Pr(1)-O(1) bond lengths are 2.69 Å. Both Pr(1)-O(4) bond lengths are 2.29 Å. All Pr(1)-O(3) bond lengths are 2.60 Å. In the second Pr site, Pr(2) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms. Both Pr(2)-O(2) bond lengths are 2.55 Å. Both Pr(2)-O(4) bond lengths are 2.34 Å. All Pr(2)-O(3) bond lengths are 2.65 Å. Sc(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form ScO6 octahedra that share corners with two equivalent Sc(1)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and edges with two equivalent Pr(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 49-55°. Both Sc(1)-O(2) bond lengths are 2.12 Å. All Sc(1)-O(3) bond lengths are 2.15 Å. Nb(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Sc(1)O6 octahedra, and edges with four equivalent Pr(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-49°. Both Nb(1)-O(1) bond lengths are 2.05 Å. All Nb(1)-O(3) bond lengths are 2.01 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Pr(1) and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded to two equivalent Pr(2) and two equivalent Sc(1) atoms to form distorted OPr2Sc2 tetrahedra that share corners with two equivalent O(4)Pr4 tetrahedra, corners with four equivalent O(2)Pr2Sc2 tetrahedra, corners with eight equivalent O(3)Pr2ScNb tetrahedra,  an edgeedge with one O(4)Pr4 tetrahedra, and edges with four equivalent O(3)Pr2ScNb tetrahedra. In the third O site, O(3) is bonded to one Pr(1), one Pr(2), one Sc(1), and one Nb(1) atom to form distorted OPr2ScNb tetrahedra that share corners with two equivalent O(2)Pr2Sc2 tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra, corners with eight equivalent O(3)Pr2ScNb tetrahedra,  an edgeedge with one O(2)Pr2Sc2 tetrahedra,  an edgeedge with one O(4)Pr4 tetrahedra, and edges with two equivalent O(3)Pr2ScNb tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Pr(1) and two equivalent Pr(2) atoms to form OPr4 tetrahedra that share corners with two equivalent O(2)Pr2Sc2 tetrahedra, corners with four equivalent O(4)Pr4 tetrahedra, corners with eight equivalent O(3)Pr2ScNb tetrahedra,  an edgeedge with one O(2)Pr2Sc2 tetrahedra, and edges with four equivalent O(3)Pr2ScNb tetrahedra.