Redetermination of catena-poly[bis[chloro(μ-pyridine N-oxide-κ2O:O)copper(II)]-di-μ-chloro]

The title compound, [Cu2Cl4(C5H5NO)(2)](n), is a one-dimensional polymer in which the Cu-II atoms are alternately bridged by two O atoms [Cu...Cu = 3.2131 (10) Angstrom] and two Cl atoms [Cu...Cu = 3.7061 (11) Angstrom]. The metal centers display a very distorted coordination geometry, with the four stronger bonds defining a CuCl2O2 polyhedron midway between square planar and tetrahedral, which serves as the base of a pyramid, while the loosely bound Cl atom in the bridge occupies the apex. The simultaneous presence of a good hydrogen-bond acceptor and an adequate C - H donor leads to a network of C-H...Cl interactions.