Poly[[tetra-kis-(μ(2)-pyrazine N,N'-dioxide-κO:O')erbium(III)] tris-(perchlorate)]

The title three-dimensional coordination network, {[Er(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), is isostructural to that of other lanthanides. The Er(+3 )cation lies on a fourfold roto-inversion axis. It is coordinated in a distorted square-anti-prismatic fashion by eight O atoms from bridging pyrazine N,N'-dioxide ligands. There are two unique pyrazine N,N'-dioxide ligands. One ring is located around an inversion center, and there is a a twofold rotation axis at the center of the other ring. There are also two unique perchlorate anions. One is centered on a twofold rotation axis and the other on a fourfold roto-inversion axis. The perchlorate anions are located in channels that run perpendicular to (001) and (110) and inter-act with the coordination network through C-H⋯O hydrogen bonds.