Er3Pd8Sb4 crystallizes in the cubic Fm-3m space group. Er(1) is bonded in a 13-coordinate geometry to four equivalent Pd(1), four equivalent Pd(2), one Sb(2), and four equivalent Sb(1) atoms. There are two inequivalent Pd sites. In the first Pd site, Pd(2) is bonded in a 6-coordinate geometry to three equivalent Er(1) and three equivalent Sb(1) atoms. In the second Pd site, Pd(1) is bonded in a 7-coordinate geometry to three equivalent Er(1), one Sb(3), and three equivalent Sb(1) atoms. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to four equivalent Er(1), four equivalent Pd(1), and four equivalent Pd(2) atoms to form SbEr4Pd8 cuboctahedra that share corners with four equivalent Sb(1)Er4Pd8 cuboctahedra, edges with two equivalent Sb(2)Er6 octahedra, and faces with eight equivalent Sb(1)Er4Pd8 cuboctahedra. In the second Sb site, Sb(2) is bonded to six equivalent Er(1) atoms to form edge-sharing SbEr6 octahedra. In the third Sb site, Sb(3) is bonded in a body-centered cubic geometry to eight equivalent Pd(1) atoms.
Er3Pd8Sb4 crystallizes in the cubic Fm-3m space group. Er(1) is bonded in a 13-coordinate geometry to four equivalent Pd(1), four equivalent Pd(2), one Sb(2), and four equivalent Sb(1) atoms. All Er(1)-Pd(1) bond lengths are 3.05 Å. All Er(1)-Pd(2) bond lengths are 3.21 Å. The Er(1)-Sb(2) bond length is 2.97 Å. All Er(1)-Sb(1) bond lengths are 3.33 Å. There are two inequivalent Pd sites. In the first Pd site, Pd(2) is bonded in a 6-coordinate geometry to three equivalent Er(1) and three equivalent Sb(1) atoms. All Pd(2)-Sb(1) bond lengths are 2.71 Å. In the second Pd site, Pd(1) is bonded in a 7-coordinate geometry to three equivalent Er(1), one Sb(3), and three equivalent Sb(1) atoms. The Pd(1)-Sb(3) bond length is 2.73 Å. All Pd(1)-Sb(1) bond lengths are 2.92 Å. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to four equivalent Er(1), four equivalent Pd(1), and four equivalent Pd(2) atoms to form SbEr4Pd8 cuboctahedra that share corners with four equivalent Sb(1)Er4Pd8 cuboctahedra, edges with two equivalent Sb(2)Er6 octahedra, and faces with eight equivalent Sb(1)Er4Pd8 cuboctahedra. In the second Sb site, Sb(2) is bonded to six equivalent Er(1) atoms to form edge-sharing SbEr6 octahedra. In the third Sb site, Sb(3) is bonded in a body-centered cubic geometry to eight equivalent Pd(1) atoms.