Ta7(Ru3B4)2 crystallizes in the hexagonal P6/m space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to twelve equivalent B(2) atoms to form face-sharing TaB12 cuboctahedra. In the second Ta site, Ta(2) is bonded in a 11-coordinate geometry to six equivalent Ru(1), one B(1), and four equivalent B(2) atoms. Ru(1) is bonded in a 9-coordinate geometry to six equivalent Ta(2), one B(2), and two equivalent B(1) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to three equivalent Ta(2) and six equivalent Ru(1) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Ta(1), four equivalent Ta(2), one Ru(1), and two equivalent B(2) atoms.
Ta7(Ru3B4)2 crystallizes in the hexagonal P6/m space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to twelve equivalent B(2) atoms to form face-sharing TaB12 cuboctahedra. All Ta(1)-B(2) bond lengths are 2.42 Å. In the second Ta site, Ta(2) is bonded in a 11-coordinate geometry to six equivalent Ru(1), one B(1), and four equivalent B(2) atoms. There are a spread of Ta(2)-Ru(1) bond distances ranging from 2.75-2.85 Å. The Ta(2)-B(1) bond length is 2.67 Å. All Ta(2)-B(2) bond lengths are 2.36 Å. Ru(1) is bonded in a 9-coordinate geometry to six equivalent Ta(2), one B(2), and two equivalent B(1) atoms. The Ru(1)-B(2) bond length is 2.50 Å. Both Ru(1)-B(1) bond lengths are 2.23 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to three equivalent Ta(2) and six equivalent Ru(1) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Ta(1), four equivalent Ta(2), one Ru(1), and two equivalent B(2) atoms. Both B(2)-B(2) bond lengths are 1.86 Å.