Yb4(FeB2)3 crystallizes in the trigonal R-3m space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 10-coordinate geometry to three equivalent Yb(2), four equivalent Fe(2), and six equivalent B(1) atoms. In the second Yb site, Yb(2) is bonded in a 13-coordinate geometry to one Yb(2), three equivalent Yb(1), three equivalent Fe(2), and six equivalent B(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted hexagonal bipyramidal geometry to two equivalent Fe(2) and six equivalent B(1) atoms. In the second Fe site, Fe(2) is bonded to three equivalent Yb(2), four equivalent Yb(1), and one Fe(1) atom to form a mixture of distorted corner and edge-sharing FeYb7Fe hexagonal bipyramids. B(1) is bonded in a 8-coordinate geometry to two equivalent Yb(1), two equivalent Yb(2), one Fe(1), and three equivalent B(1) atoms.
Yb4(FeB2)3 crystallizes in the trigonal R-3m space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 10-coordinate geometry to three equivalent Yb(2), four equivalent Fe(2), and six equivalent B(1) atoms. All Yb(1)-Yb(2) bond lengths are 3.20 Å. There is one shorter (2.90 Å) and three longer (3.20 Å) Yb(1)-Fe(2) bond lengths. All Yb(1)-B(1) bond lengths are 2.78 Å. In the second Yb site, Yb(2) is bonded in a 13-coordinate geometry to one Yb(2), three equivalent Yb(1), three equivalent Fe(2), and six equivalent B(1) atoms. The Yb(2)-Yb(2) bond length is 3.29 Å. All Yb(2)-Fe(2) bond lengths are 3.21 Å. All Yb(2)-B(1) bond lengths are 2.71 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted hexagonal bipyramidal geometry to two equivalent Fe(2) and six equivalent B(1) atoms. Both Fe(1)-Fe(2) bond lengths are 2.34 Å. All Fe(1)-B(1) bond lengths are 1.96 Å. In the second Fe site, Fe(2) is bonded to three equivalent Yb(2), four equivalent Yb(1), and one Fe(1) atom to form a mixture of distorted corner and edge-sharing FeYb7Fe hexagonal bipyramids. B(1) is bonded in a 8-coordinate geometry to two equivalent Yb(1), two equivalent Yb(2), one Fe(1), and three equivalent B(1) atoms. There is one shorter (1.62 Å) and two longer (1.96 Å) B(1)-B(1) bond lengths.