Er7(AgTe)2 crystallizes in the orthorhombic Imm2 space group. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a distorted square co-planar geometry to three equivalent Ag(1) and two equivalent Te(2) atoms. In the second Er site, Er(2) is bonded in a 3-coordinate geometry to two equivalent Ag(1), one Te(2), and two equivalent Te(1) atoms. In the third Er site, Er(3) is bonded to two equivalent Ag(1), one Te(2), and two equivalent Te(1) atoms to form a mixture of distorted face, corner, and edge-sharing ErAg2Te3 trigonal bipyramids. In the fourth Er site, Er(4) is bonded in a 4-coordinate geometry to three equivalent Ag(1) and one Te(1) atom. Ag(1) is bonded in a 9-coordinate geometry to one Er(2), two equivalent Er(3), three equivalent Er(1), and three equivalent Er(4) atoms. There are two inequivalent Te sites. In the first Te site, Te(1) is bonded in a 8-coordinate geometry to two equivalent Er(2), two equivalent Er(4), and four equivalent Er(3) atoms. In the second Te site, Te(2) is bonded in a 7-coordinate geometry to one Er(2), two equivalent Er(3), and four equivalent Er(1) atoms.
Er7(AgTe)2 crystallizes in the orthorhombic Imm2 space group. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a distorted square co-planar geometry to three equivalent Ag(1) and two equivalent Te(2) atoms. There are two shorter (2.99 Å) and one longer (3.71 Å) Er(1)-Ag(1) bond length. Both Er(1)-Te(2) bond lengths are 3.10 Å. In the second Er site, Er(2) is bonded in a 3-coordinate geometry to two equivalent Ag(1), one Te(2), and two equivalent Te(1) atoms. Both Er(2)-Ag(1) bond lengths are 3.69 Å. The Er(2)-Te(2) bond length is 3.28 Å. Both Er(2)-Te(1) bond lengths are 3.22 Å. In the third Er site, Er(3) is bonded to two equivalent Ag(1), one Te(2), and two equivalent Te(1) atoms to form a mixture of distorted face, corner, and edge-sharing ErAg2Te3 trigonal bipyramids. Both Er(3)-Ag(1) bond lengths are 2.94 Å. The Er(3)-Te(2) bond length is 3.08 Å. Both Er(3)-Te(1) bond lengths are 3.15 Å. In the fourth Er site, Er(4) is bonded in a 4-coordinate geometry to three equivalent Ag(1) and one Te(1) atom. There are two shorter (2.87 Å) and one longer (3.18 Å) Er(4)-Ag(1) bond length. The Er(4)-Te(1) bond length is 3.14 Å. Ag(1) is bonded in a 9-coordinate geometry to one Er(2), two equivalent Er(3), three equivalent Er(1), and three equivalent Er(4) atoms. There are two inequivalent Te sites. In the first Te site, Te(1) is bonded in a 8-coordinate geometry to two equivalent Er(2), two equivalent Er(4), and four equivalent Er(3) atoms. In the second Te site, Te(2) is bonded in a 7-coordinate geometry to one Er(2), two equivalent Er(3), and four equivalent Er(1) atoms.