Er3Rh3Ga8 crystallizes in the orthorhombic Immm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to four equivalent Ga(1) and eight equivalent Ga(2) atoms to form distorted face-sharing ErGa12 cuboctahedra. In the second Er site, Er(2) is bonded in a 12-coordinate geometry to two equivalent Rh(1), two equivalent Rh(2), four equivalent Ga(1), and four equivalent Ga(2) atoms. There are two inequivalent Rh sites. In the first Rh site, Rh(1) is bonded in a 8-coordinate geometry to four equivalent Er(2) and four equivalent Ga(1) atoms. In the second Rh site, Rh(2) is bonded in a 8-coordinate geometry to two equivalent Er(2), two equivalent Ga(2), and four equivalent Ga(1) atoms. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to one Er(1), two equivalent Er(2), one Rh(1), two equivalent Rh(2), and three equivalent Ga(2) atoms. In the second Ga site, Ga(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), one Rh(2), one Ga(2), and three equivalent Ga(1) atoms.
Er3Rh3Ga8 crystallizes in the orthorhombic Immm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to four equivalent Ga(1) and eight equivalent Ga(2) atoms to form distorted face-sharing ErGa12 cuboctahedra. All Er(1)-Ga(1) bond lengths are 3.20 Å. All Er(1)-Ga(2) bond lengths are 3.17 Å. In the second Er site, Er(2) is bonded in a 12-coordinate geometry to two equivalent Rh(1), two equivalent Rh(2), four equivalent Ga(1), and four equivalent Ga(2) atoms. Both Er(2)-Rh(1) bond lengths are 2.97 Å. Both Er(2)-Rh(2) bond lengths are 2.98 Å. All Er(2)-Ga(1) bond lengths are 3.04 Å. All Er(2)-Ga(2) bond lengths are 3.15 Å. There are two inequivalent Rh sites. In the first Rh site, Rh(1) is bonded in a 8-coordinate geometry to four equivalent Er(2) and four equivalent Ga(1) atoms. All Rh(1)-Ga(1) bond lengths are 2.61 Å. In the second Rh site, Rh(2) is bonded in a 8-coordinate geometry to two equivalent Er(2), two equivalent Ga(2), and four equivalent Ga(1) atoms. Both Rh(2)-Ga(2) bond lengths are 2.55 Å. All Rh(2)-Ga(1) bond lengths are 2.59 Å. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to one Er(1), two equivalent Er(2), one Rh(1), two equivalent Rh(2), and three equivalent Ga(2) atoms. There are two shorter (2.65 Å) and one longer (2.70 Å) Ga(1)-Ga(2) bond length. In the second Ga site, Ga(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), one Rh(2), one Ga(2), and three equivalent Ga(1) atoms. The Ga(2)-Ga(2) bond length is 2.53 Å.