Ba2GdCu3SO6 crystallizes in the orthorhombic Pmmm space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent S(1), two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. Gd(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted corner-sharing CuO5 square pyramids. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent S(1) and two equivalent O(3) atoms. S(1) is bonded to four equivalent Ba(1) and two equivalent Cu(2) atoms to form distorted SBa4Cu2 octahedra that share corners with two equivalent S(1)Ba4Cu2 octahedra, corners with four equivalent O(2)Ba2Gd2Cu2 octahedra, edges with two equivalent S(1)Ba4Cu2 octahedra, and edges with two equivalent O(2)Ba2Gd2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Gd(1), and two equivalent Cu(1) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Gd(1), and two equivalent Cu(1) atoms to form distorted OBa2Gd2Cu2 octahedra that share corners with two equivalent S(1)Ba4Cu2 octahedra, corners with four equivalent O(2)Ba2Gd2Cu2 octahedra,  an edgeedge with one S(1)Ba4Cu2 octahedra, and edges with three equivalent O(2)Ba2Gd2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Cu(1), and one Cu(2) atom.
Ba2GdCu3SO6 crystallizes in the orthorhombic Pmmm space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent S(1), two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. Both Ba(1)-S(1) bond lengths are 3.14 Å. Both Ba(1)-O(1) bond lengths are 3.06 Å. Both Ba(1)-O(2) bond lengths are 2.90 Å. All Ba(1)-O(3) bond lengths are 2.89 Å. Gd(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. All Gd(1)-O(1) bond lengths are 2.55 Å. All Gd(1)-O(2) bond lengths are 2.43 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted corner-sharing CuO5 square pyramids. The Cu(1)-O(3) bond length is 2.56 Å. Both Cu(1)-O(1) bond lengths are 1.93 Å. Both Cu(1)-O(2) bond lengths are 2.10 Å. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent S(1) and two equivalent O(3) atoms. Both Cu(2)-S(1) bond lengths are 2.10 Å. Both Cu(2)-O(3) bond lengths are 1.92 Å. S(1) is bonded to four equivalent Ba(1) and two equivalent Cu(2) atoms to form distorted SBa4Cu2 octahedra that share corners with two equivalent S(1)Ba4Cu2 octahedra, corners with four equivalent O(2)Ba2Gd2Cu2 octahedra, edges with two equivalent S(1)Ba4Cu2 octahedra, and edges with two equivalent O(2)Ba2Gd2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Gd(1), and two equivalent Cu(1) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Gd(1), and two equivalent Cu(1) atoms to form distorted OBa2Gd2Cu2 octahedra that share corners with two equivalent S(1)Ba4Cu2 octahedra, corners with four equivalent O(2)Ba2Gd2Cu2 octahedra,  an edgeedge with one S(1)Ba4Cu2 octahedra, and edges with three equivalent O(2)Ba2Gd2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Cu(1), and one Cu(2) atom.