Eu3(Rh4B3)2 crystallizes in the orthorhombic Fmmm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 16-coordinate geometry to one Eu(2), two equivalent Rh(3), four equivalent Rh(1), four equivalent Rh(2), and six equivalent B(2) atoms. In the second Eu site, Eu(2) is bonded in a 20-coordinate geometry to two equivalent Eu(1), four equivalent Rh(3), eight equivalent Rh(1), and six equivalent B(1) atoms. There are three inequivalent Rh sites. In the first Rh site, Rh(1) is bonded in a distorted square co-planar geometry to two equivalent Eu(1), two equivalent Eu(2), two equivalent B(1), and two equivalent B(2) atoms. In the second Rh site, Rh(2) is bonded in a 4-coordinate geometry to four equivalent Eu(1) and four equivalent B(2) atoms. In the third Rh site, Rh(3) is bonded in a distorted square co-planar geometry to two equivalent Eu(1), two equivalent Eu(2), two equivalent B(1), and two equivalent B(2) atoms. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to three equivalent Eu(2), two equivalent Rh(3), and four equivalent Rh(1) atoms. In the second B site, B(2) is bonded in a 5-coordinate geometry to three equivalent Eu(1), one Rh(3), two equivalent Rh(1), and two equivalent Rh(2) atoms. In the third B site, B(1) is bonded in a 6-coordinate geometry to three equivalent Eu(2), two equivalent Rh(3), and four equivalent Rh(1) atoms.
Eu3(Rh4B3)2 crystallizes in the orthorhombic Fmmm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 16-coordinate geometry to one Eu(2), two equivalent Rh(3), four equivalent Rh(1), four equivalent Rh(2), and six equivalent B(2) atoms. The Eu(1)-Eu(2) bond length is 3.15 Å. Both Eu(1)-Rh(3) bond lengths are 3.23 Å. All Eu(1)-Rh(1) bond lengths are 3.30 Å. All Eu(1)-Rh(2) bond lengths are 3.05 Å. There are two shorter (2.97 Å) and four longer (3.21 Å) Eu(1)-B(2) bond lengths. In the second Eu site, Eu(2) is bonded in a 20-coordinate geometry to two equivalent Eu(1), four equivalent Rh(3), eight equivalent Rh(1), and six equivalent B(1) atoms. All Eu(2)-Rh(3) bond lengths are 3.16 Å. All Eu(2)-Rh(1) bond lengths are 3.18 Å. There are four shorter (3.22 Å) and two longer (3.30 Å) Eu(2)-B(1) bond lengths. There are three inequivalent Rh sites. In the first Rh site, Rh(1) is bonded in a distorted square co-planar geometry to two equivalent Eu(1), two equivalent Eu(2), two equivalent B(1), and two equivalent B(2) atoms. Both Rh(1)-B(1) bond lengths are 2.18 Å. Both Rh(1)-B(2) bond lengths are 2.21 Å. In the second Rh site, Rh(2) is bonded in a 4-coordinate geometry to four equivalent Eu(1) and four equivalent B(2) atoms. All Rh(2)-B(2) bond lengths are 2.13 Å. In the third Rh site, Rh(3) is bonded in a distorted square co-planar geometry to two equivalent Eu(1), two equivalent Eu(2), two equivalent B(1), and two equivalent B(2) atoms. Both Rh(3)-B(1) bond lengths are 2.21 Å. Both Rh(3)-B(2) bond lengths are 2.14 Å. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to three equivalent Eu(2), two equivalent Rh(3), and four equivalent Rh(1) atoms. In the second B site, B(2) is bonded in a 5-coordinate geometry to three equivalent Eu(1), one Rh(3), two equivalent Rh(1), and two equivalent Rh(2) atoms. In the third B site, B(1) is bonded in a 6-coordinate geometry to three equivalent Eu(2), two equivalent Rh(3), and four equivalent Rh(1) atoms. There are two shorter (3.22 Å) and one longer (3.30 Å) B(1)-Eu(2) bond length. Both B(1)-Rh(3) bond lengths are 2.21 Å. All B(1)-Rh(1) bond lengths are 2.18 Å.