Ba2U2O3 crystallizes in the monoclinic Pm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a linear geometry to one O(1) and one O(3) atom. In the second Ba site, Ba(2) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(2) atoms. There are two inequivalent U sites. In the first U site, U(1) is bonded in a T-shaped geometry to one O(2) and two equivalent O(1) atoms. In the second U site, U(2) is bonded in a distorted trigonal non-coplanar geometry to one O(2) and two equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), and two equivalent U(1) atoms to form a mixture of distorted corner and edge-sharing OBa2U2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Ba(2), one U(1), and one U(2) atom to form a mixture of distorted corner and edge-sharing OBa2U2 tetrahedra. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), and two equivalent U(2) atoms to form distorted corner-sharing OBa2U2 trigonal pyramids.
Ba2U2O3 crystallizes in the monoclinic Pm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a linear geometry to one O(1) and one O(3) atom. The Ba(1)-O(1) bond length is 2.75 Å. The Ba(1)-O(3) bond length is 2.86 Å. In the second Ba site, Ba(2) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(2) atoms. The Ba(2)-O(1) bond length is 2.97 Å. The Ba(2)-O(3) bond length is 2.88 Å. Both Ba(2)-O(2) bond lengths are 2.80 Å. There are two inequivalent U sites. In the first U site, U(1) is bonded in a T-shaped geometry to one O(2) and two equivalent O(1) atoms. The U(1)-O(2) bond length is 2.16 Å. Both U(1)-O(1) bond lengths are 2.16 Å. In the second U site, U(2) is bonded in a distorted trigonal non-coplanar geometry to one O(2) and two equivalent O(3) atoms. The U(2)-O(2) bond length is 2.16 Å. Both U(2)-O(3) bond lengths are 2.18 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), and two equivalent U(1) atoms to form a mixture of distorted corner and edge-sharing OBa2U2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Ba(2), one U(1), and one U(2) atom to form a mixture of distorted corner and edge-sharing OBa2U2 tetrahedra. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), and two equivalent U(2) atoms to form distorted corner-sharing OBa2U2 trigonal pyramids.