Ba8PdU2Se12(Se2)2 crystallizes in the orthorhombic Pnnm space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and three equivalent Se(5) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(5), and four equivalent Se(4) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one Pd(1), one Se(1), two equivalent Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. U(1) is bonded in an octahedral geometry to two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. Pd(1) is bonded in a 6-coordinate geometry to two equivalent Ba(3) and four equivalent Se(3) atoms. There are five inequivalent Se sites. In the first Se site, Se(4) is bonded to one Ba(3), two equivalent Ba(1), two equivalent Ba(2), and one U(1) atom to form a mixture of distorted edge, face, and corner-sharing SeBa5U octahedra. The corner-sharing octahedral tilt angles range from 33-57°. In the second Se site, Se(5) is bonded to one Ba(2), one Ba(3), three equivalent Ba(1), and one U(1) atom to form a mixture of distorted edge, face, and corner-sharing SeBa5U octahedra. The corner-sharing octahedral tilt angles range from 3-57°. In the third Se site, Se(1) is bonded in a 6-coordinate geometry to one Ba(3), two equivalent Ba(1), two equivalent Ba(2), and one Se(1) atom. In the fourth Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), and one Se(2) atom. In the fifth Se site, Se(3) is bonded in a 5-coordinate geometry to one Ba(3), two equivalent Ba(1), one U(1), and one Pd(1) atom.
Ba8PdU2Se12(Se2)2 crystallizes in the orthorhombic Pnnm space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and three equivalent Se(5) atoms. The Ba(1)-Se(1) bond length is 3.75 Å. The Ba(1)-Se(2) bond length is 3.62 Å. There is one shorter (3.55 Å) and one longer (3.57 Å) Ba(1)-Se(3) bond length. There is one shorter (3.44 Å) and one longer (3.46 Å) Ba(1)-Se(4) bond length. There are a spread of Ba(1)-Se(5) bond distances ranging from 3.36-3.43 Å. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(5), and four equivalent Se(4) atoms. There is one shorter (3.21 Å) and one longer (3.27 Å) Ba(2)-Se(1) bond length. Both Ba(2)-Se(5) bond lengths are 3.57 Å. There are two shorter (3.44 Å) and two longer (3.61 Å) Ba(2)-Se(4) bond lengths. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one Pd(1), one Se(1), two equivalent Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. The Ba(3)-Pd(1) bond length is 3.20 Å. The Ba(3)-Se(1) bond length is 3.77 Å. There is one shorter (3.22 Å) and one longer (3.26 Å) Ba(3)-Se(2) bond length. Both Ba(3)-Se(3) bond lengths are 3.65 Å. Both Ba(3)-Se(4) bond lengths are 3.32 Å. Both Ba(3)-Se(5) bond lengths are 3.60 Å. U(1) is bonded in an octahedral geometry to two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. Both U(1)-Se(3) bond lengths are 2.73 Å. Both U(1)-Se(4) bond lengths are 2.73 Å. Both U(1)-Se(5) bond lengths are 2.83 Å. Pd(1) is bonded in a 6-coordinate geometry to two equivalent Ba(3) and four equivalent Se(3) atoms. All Pd(1)-Se(3) bond lengths are 2.55 Å. There are five inequivalent Se sites. In the first Se site, Se(4) is bonded to one Ba(3), two equivalent Ba(1), two equivalent Ba(2), and one U(1) atom to form a mixture of distorted edge, face, and corner-sharing SeBa5U octahedra. The corner-sharing octahedral tilt angles range from 33-57°. In the second Se site, Se(5) is bonded to one Ba(2), one Ba(3), three equivalent Ba(1), and one U(1) atom to form a mixture of distorted edge, face, and corner-sharing SeBa5U octahedra. The corner-sharing octahedral tilt angles range from 3-57°. In the third Se site, Se(1) is bonded in a 6-coordinate geometry to one Ba(3), two equivalent Ba(1), two equivalent Ba(2), and one Se(1) atom. The Se(1)-Se(1) bond length is 2.43 Å. In the fourth Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), and one Se(2) atom. The Se(2)-Se(2) bond length is 2.44 Å. In the fifth Se site, Se(3) is bonded in a 5-coordinate geometry to one Ba(3), two equivalent Ba(1), one U(1), and one Pd(1) atom.