BaSc2O4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one O(2), one O(3), one O(6), two equivalent O(1), two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms. In the second Ba site, Ba(2) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(5), two equivalent O(7), and four equivalent O(4) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, corners with six equivalent Sc(1)O6 pentagonal pyramids, and faces with six equivalent Sc(3)O6 octahedra. There are three inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms to form distorted ScO6 pentagonal pyramids that share corners with three equivalent Ba(2)O12 cuboctahedra,  a cornercorner with one Sc(1)O6 pentagonal pyramid,  an edgeedge with one Sc(1)O6 pentagonal pyramid, and  a faceface with one Sc(3)O6 octahedra. In the second Sc site, Sc(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms. In the third Sc site, Sc(3) is bonded to one O(1), one O(2), one O(5), one O(7), and two equivalent O(4) atoms to form ScO6 octahedra that share corners with three equivalent Sc(3)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, and  a faceface with one Sc(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 7-11°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Sc(1), one Sc(2), and one Sc(3) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sc(3) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Sc(1), and two equivalent Sc(2) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sc(3) atoms. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Sc(1), one Sc(2), and one Sc(3) atom. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to one Ba(1), two equivalent Sc(1), and two equivalent Sc(2) atoms. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ba(2), two equivalent Ba(1), one Sc(1), one Sc(2), and one Sc(3) atom.
BaSc2O4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 11-coordinate geometry to one O(2), one O(3), one O(6), two equivalent O(1), two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms. The Ba(1)-O(2) bond length is 2.85 Å. The Ba(1)-O(3) bond length is 3.33 Å. The Ba(1)-O(6) bond length is 3.43 Å. There is one shorter (2.71 Å) and one longer (3.14 Å) Ba(1)-O(1) bond length. There is one shorter (2.83 Å) and one longer (2.90 Å) Ba(1)-O(4) bond length. There is one shorter (2.69 Å) and one longer (3.07 Å) Ba(1)-O(5) bond length. There is one shorter (2.71 Å) and one longer (3.08 Å) Ba(1)-O(7) bond length. In the second Ba site, Ba(2) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(5), two equivalent O(7), and four equivalent O(4) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, corners with six equivalent Sc(1)O6 pentagonal pyramids, and faces with six equivalent Sc(3)O6 octahedra. Both Ba(2)-O(1) bond lengths are 3.10 Å. There is one shorter (2.74 Å) and one longer (3.09 Å) Ba(2)-O(2) bond length. Both Ba(2)-O(5) bond lengths are 3.11 Å. Both Ba(2)-O(7) bond lengths are 3.24 Å. There are two shorter (2.74 Å) and two longer (3.00 Å) Ba(2)-O(4) bond lengths. There are three inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms to form distorted ScO6 pentagonal pyramids that share corners with three equivalent Ba(2)O12 cuboctahedra,  a cornercorner with one Sc(1)O6 pentagonal pyramid,  an edgeedge with one Sc(1)O6 pentagonal pyramid, and  a faceface with one Sc(3)O6 octahedra. The Sc(1)-O(1) bond length is 2.21 Å. The Sc(1)-O(3) bond length is 2.08 Å. The Sc(1)-O(5) bond length is 2.15 Å. The Sc(1)-O(7) bond length is 2.13 Å. There is one shorter (2.16 Å) and one longer (2.19 Å) Sc(1)-O(6) bond length. In the second Sc site, Sc(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(5), one O(7), and two equivalent O(6) atoms. The Sc(2)-O(1) bond length is 2.04 Å. The Sc(2)-O(3) bond length is 2.66 Å. The Sc(2)-O(5) bond length is 2.06 Å. The Sc(2)-O(7) bond length is 2.02 Å. There is one shorter (2.19 Å) and one longer (2.25 Å) Sc(2)-O(6) bond length. In the third Sc site, Sc(3) is bonded to one O(1), one O(2), one O(5), one O(7), and two equivalent O(4) atoms to form ScO6 octahedra that share corners with three equivalent Sc(3)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, and  a faceface with one Sc(1)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 7-11°. The Sc(3)-O(1) bond length is 2.18 Å. The Sc(3)-O(2) bond length is 2.02 Å. The Sc(3)-O(5) bond length is 2.22 Å. The Sc(3)-O(7) bond length is 2.23 Å. Both Sc(3)-O(4) bond lengths are 2.02 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Sc(1), one Sc(2), and one Sc(3) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sc(3) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Sc(1), and two equivalent Sc(2) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sc(3) atoms. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Sc(1), one Sc(2), and one Sc(3) atom. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to one Ba(1), two equivalent Sc(1), and two equivalent Sc(2) atoms. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ba(2), two equivalent Ba(1), one Sc(1), one Sc(2), and one Sc(3) atom.