Er6Fe23 crystallizes in the cubic Fm-3m space group. Er(1) is bonded in a 12-coordinate geometry to four equivalent Fe(1), four equivalent Fe(3), and four equivalent Fe(4) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(4) is bonded in a 13-coordinate geometry to three equivalent Er(1), one Fe(2), three equivalent Fe(1), three equivalent Fe(3), and three equivalent Fe(4) atoms. In the second Fe site, Fe(1) is bonded in a distorted q6 geometry to three equivalent Er(1), three equivalent Fe(1), three equivalent Fe(3), and three equivalent Fe(4) atoms. In the third Fe site, Fe(2) is bonded in a body-centered cubic geometry to eight equivalent Fe(4) atoms. In the fourth Fe site, Fe(3) is bonded to four equivalent Er(1), four equivalent Fe(1), and four equivalent Fe(4) atoms to form a mixture of corner and face-sharing FeEr4Fe8 cuboctahedra.
Er6Fe23 crystallizes in the cubic Fm-3m space group. Er(1) is bonded in a 12-coordinate geometry to four equivalent Fe(1), four equivalent Fe(3), and four equivalent Fe(4) atoms. All Er(1)-Fe(1) bond lengths are 2.99 Å. All Er(1)-Fe(3) bond lengths are 3.03 Å. All Er(1)-Fe(4) bond lengths are 2.88 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(4) is bonded in a 13-coordinate geometry to three equivalent Er(1), one Fe(2), three equivalent Fe(1), three equivalent Fe(3), and three equivalent Fe(4) atoms. The Fe(4)-Fe(2) bond length is 2.52 Å. All Fe(4)-Fe(1) bond lengths are 2.59 Å. All Fe(4)-Fe(3) bond lengths are 2.61 Å. All Fe(4)-Fe(4) bond lengths are 2.90 Å. In the second Fe site, Fe(1) is bonded in a distorted q6 geometry to three equivalent Er(1), three equivalent Fe(1), three equivalent Fe(3), and three equivalent Fe(4) atoms. All Fe(1)-Fe(1) bond lengths are 2.53 Å. All Fe(1)-Fe(3) bond lengths are 2.45 Å. In the third Fe site, Fe(2) is bonded in a body-centered cubic geometry to eight equivalent Fe(4) atoms. In the fourth Fe site, Fe(3) is bonded to four equivalent Er(1), four equivalent Fe(1), and four equivalent Fe(4) atoms to form a mixture of corner and face-sharing FeEr4Fe8 cuboctahedra.