Er2ReB6 crystallizes in the orthorhombic Pbam space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 14-coordinate geometry to three equivalent Re(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), two equivalent B(5), two equivalent B(6), and four equivalent B(1) atoms. In the second Er site, Er(2) is bonded in a 14-coordinate geometry to two equivalent Re(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), two equivalent B(5), and four equivalent B(6) atoms. Re(1) is bonded in a 15-coordinate geometry to two equivalent Er(2), three equivalent Er(1), two equivalent B(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), and two equivalent B(5) atoms. There are six inequivalent B sites. In the first B site, B(6) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one B(2), one B(4), and one B(6) atom. In the second B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Er(1), two equivalent Re(1), one B(1), one B(2), and one B(5) atom. In the third B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(1), one B(3), and one B(6) atom. In the fourth B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(2), one B(4), and one B(5) atom. In the fifth B site, B(4) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(3), one B(5), and one B(6) atom. In the sixth B site, B(5) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(1), one B(3), and one B(4) atom.
Er2ReB6 crystallizes in the orthorhombic Pbam space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 14-coordinate geometry to three equivalent Re(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), two equivalent B(5), two equivalent B(6), and four equivalent B(1) atoms. There are two shorter (3.06 Å) and one longer (3.18 Å) Er(1)-Re(1) bond length. Both Er(1)-B(2) bond lengths are 2.73 Å. Both Er(1)-B(3) bond lengths are 2.76 Å. Both Er(1)-B(4) bond lengths are 2.78 Å. Both Er(1)-B(5) bond lengths are 2.74 Å. Both Er(1)-B(6) bond lengths are 2.82 Å. There are two shorter (2.77 Å) and two longer (2.78 Å) Er(1)-B(1) bond lengths. In the second Er site, Er(2) is bonded in a 14-coordinate geometry to two equivalent Re(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), two equivalent B(5), and four equivalent B(6) atoms. There is one shorter (2.82 Å) and one longer (2.83 Å) Er(2)-Re(1) bond length. Both Er(2)-B(2) bond lengths are 2.60 Å. Both Er(2)-B(3) bond lengths are 2.58 Å. Both Er(2)-B(4) bond lengths are 2.58 Å. Both Er(2)-B(5) bond lengths are 2.60 Å. All Er(2)-B(6) bond lengths are 2.60 Å. Re(1) is bonded in a 15-coordinate geometry to two equivalent Er(2), three equivalent Er(1), two equivalent B(1), two equivalent B(2), two equivalent B(3), two equivalent B(4), and two equivalent B(5) atoms. Both Re(1)-B(1) bond lengths are 2.37 Å. Both Re(1)-B(2) bond lengths are 2.37 Å. Both Re(1)-B(3) bond lengths are 2.39 Å. Both Re(1)-B(4) bond lengths are 2.40 Å. Both Re(1)-B(5) bond lengths are 2.35 Å. There are six inequivalent B sites. In the first B site, B(6) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one B(2), one B(4), and one B(6) atom. The B(6)-B(2) bond length is 1.86 Å. The B(6)-B(4) bond length is 1.83 Å. The B(6)-B(6) bond length is 1.92 Å. In the second B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Er(1), two equivalent Re(1), one B(1), one B(2), and one B(5) atom. The B(1)-B(1) bond length is 1.82 Å. The B(1)-B(2) bond length is 1.80 Å. The B(1)-B(5) bond length is 1.79 Å. In the third B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(1), one B(3), and one B(6) atom. The B(2)-B(3) bond length is 1.81 Å. In the fourth B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(2), one B(4), and one B(5) atom. The B(3)-B(4) bond length is 1.73 Å. The B(3)-B(5) bond length is 1.83 Å. In the fifth B site, B(4) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(3), one B(5), and one B(6) atom. The B(4)-B(5) bond length is 1.80 Å. In the sixth B site, B(5) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Re(1), one B(1), one B(3), and one B(4) atom.