MgEr2Ni2 crystallizes in the tetragonal P4/mbm space group. Mg(1) is bonded in a distorted square co-planar geometry to four equivalent Ni(1) atoms. Er(1) is bonded in a 6-coordinate geometry to six equivalent Ni(1) atoms. Ni(1) is bonded in a 9-coordinate geometry to two equivalent Mg(1), six equivalent Er(1), and one Ni(1) atom.
MgEr2Ni2 crystallizes in the tetragonal P4/mbm space group. Mg(1) is bonded in a distorted square co-planar geometry to four equivalent Ni(1) atoms. All Mg(1)-Ni(1) bond lengths are 2.89 Å. Er(1) is bonded in a 6-coordinate geometry to six equivalent Ni(1) atoms. All Er(1)-Ni(1) bond lengths are 2.82 Å. Ni(1) is bonded in a 9-coordinate geometry to two equivalent Mg(1), six equivalent Er(1), and one Ni(1) atom. The Ni(1)-Ni(1) bond length is 2.46 Å.