Re6Se7Br4 crystallizes in the trigonal R3c space group. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded to one Se(2), one Se(3), two equivalent Se(1), and one Br(1) atom to form distorted ReSe4Br square pyramids that share  a cornercorner with one Re(2)Se3Br2 square pyramid, edges with two equivalent Re(2)Se3Br2 square pyramids, and edges with two equivalent Re(1)Se4Br square pyramids. In the second Re site, Re(2) is bonded to one Se(1), two equivalent Se(2), one Br(1), and one Br(2) atom to form distorted ReSe3Br2 square pyramids that share  a cornercorner with one Re(1)Se4Br square pyramid, edges with two equivalent Re(2)Se3Br2 square pyramids, and edges with two equivalent Re(1)Se4Br square pyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Re(2) and two equivalent Re(1) atoms. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Re(1) and two equivalent Re(2) atoms. In the third Se site, Se(3) is bonded in a 3-coordinate geometry to three equivalent Re(1) atoms. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a bent 120 degrees geometry to one Re(1) and one Re(2) atom. In the second Br site, Br(2) is bonded in a 3-coordinate geometry to three equivalent Re(2) atoms.
Re6Se7Br4 crystallizes in the trigonal R3c space group. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded to one Se(2), one Se(3), two equivalent Se(1), and one Br(1) atom to form distorted ReSe4Br square pyramids that share  a cornercorner with one Re(2)Se3Br2 square pyramid, edges with two equivalent Re(2)Se3Br2 square pyramids, and edges with two equivalent Re(1)Se4Br square pyramids. The Re(1)-Se(2) bond length is 2.51 Å. The Re(1)-Se(3) bond length is 2.53 Å. Both Re(1)-Se(1) bond lengths are 2.53 Å. The Re(1)-Br(1) bond length is 2.65 Å. In the second Re site, Re(2) is bonded to one Se(1), two equivalent Se(2), one Br(1), and one Br(2) atom to form distorted ReSe3Br2 square pyramids that share  a cornercorner with one Re(1)Se4Br square pyramid, edges with two equivalent Re(2)Se3Br2 square pyramids, and edges with two equivalent Re(1)Se4Br square pyramids. The Re(2)-Se(1) bond length is 2.48 Å. Both Re(2)-Se(2) bond lengths are 2.53 Å. The Re(2)-Br(1) bond length is 2.63 Å. The Re(2)-Br(2) bond length is 2.65 Å. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Re(2) and two equivalent Re(1) atoms. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Re(1) and two equivalent Re(2) atoms. In the third Se site, Se(3) is bonded in a 3-coordinate geometry to three equivalent Re(1) atoms. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a bent 120 degrees geometry to one Re(1) and one Re(2) atom. In the second Br site, Br(2) is bonded in a 3-coordinate geometry to three equivalent Re(2) atoms.