Er3In5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 9-coordinate geometry to one In(1), four equivalent In(2), and four equivalent In(3) atoms. In the second Er site, Er(2) is bonded in a 10-coordinate geometry to two equivalent In(1), four equivalent In(2), and four equivalent In(3) atoms. There are three inequivalent In sites. In the first In site, In(1) is bonded in a 11-coordinate geometry to one Er(1), four equivalent Er(2), two equivalent In(2), and four equivalent In(3) atoms. In the second In site, In(2) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one In(1), one In(2), and two equivalent In(3) atoms. In the third In site, In(3) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Er(2), two equivalent In(1), and two equivalent In(2) atoms.
Er3In5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 9-coordinate geometry to one In(1), four equivalent In(2), and four equivalent In(3) atoms. The Er(1)-In(1) bond length is 3.09 Å. There are two shorter (3.08 Å) and two longer (3.27 Å) Er(1)-In(2) bond lengths. There are two shorter (3.08 Å) and two longer (3.37 Å) Er(1)-In(3) bond lengths. In the second Er site, Er(2) is bonded in a 10-coordinate geometry to two equivalent In(1), four equivalent In(2), and four equivalent In(3) atoms. Both Er(2)-In(1) bond lengths are 3.25 Å. There are two shorter (3.19 Å) and two longer (3.30 Å) Er(2)-In(2) bond lengths. There are two shorter (3.16 Å) and two longer (3.47 Å) Er(2)-In(3) bond lengths. There are three inequivalent In sites. In the first In site, In(1) is bonded in a 11-coordinate geometry to one Er(1), four equivalent Er(2), two equivalent In(2), and four equivalent In(3) atoms. Both In(1)-In(2) bond lengths are 3.21 Å. There are two shorter (3.12 Å) and two longer (3.24 Å) In(1)-In(3) bond lengths. In the second In site, In(2) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one In(1), one In(2), and two equivalent In(3) atoms. The In(2)-In(2) bond length is 3.20 Å. Both In(2)-In(3) bond lengths are 3.00 Å. In the third In site, In(3) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Er(2), two equivalent In(1), and two equivalent In(2) atoms.