Er2Au2Sn crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to six equivalent Au(1) and four equivalent Sn(1) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to six equivalent Au(1) and four equivalent Sn(1) atoms. Au(1) is bonded in a 8-coordinate geometry to three equivalent Er(1), three equivalent Er(2), and two equivalent Sn(1) atoms. Sn(1) is bonded to four equivalent Er(1), four equivalent Er(2), and four equivalent Au(1) atoms to form a mixture of distorted corner and face-sharing SnEr8Au4 cuboctahedra.
Er2Au2Sn crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to six equivalent Au(1) and four equivalent Sn(1) atoms. There are two shorter (2.95 Å) and four longer (3.00 Å) Er(1)-Au(1) bond lengths. All Er(1)-Sn(1) bond lengths are 3.44 Å. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to six equivalent Au(1) and four equivalent Sn(1) atoms. There are two shorter (2.92 Å) and four longer (3.07 Å) Er(2)-Au(1) bond lengths. All Er(2)-Sn(1) bond lengths are 3.51 Å. Au(1) is bonded in a 8-coordinate geometry to three equivalent Er(1), three equivalent Er(2), and two equivalent Sn(1) atoms. Both Au(1)-Sn(1) bond lengths are 3.12 Å. Sn(1) is bonded to four equivalent Er(1), four equivalent Er(2), and four equivalent Au(1) atoms to form a mixture of distorted corner and face-sharing SnEr8Au4 cuboctahedra.