catena-Poly[[bis(pyridine-κN)nickel(II)]-di-μ-azido-κ4N1:N3-[bis(pyridine-κN)nickel(II)]-di-μ-azido-κ4N1:N1]

In the structure of the title compound, [Ni-2(N-3)(4)(C5H5N)(4)](n), neutral chains of Ni-II atoms are bridged alternately by double end-on and double end-to-end azide bridges. Each Ni-II center is located on a crystallographic general position and in a slightly distorted octahedral coordination environment with two pyridine ligands in the trans positions. Both end-on and end-to-end double azide bridges become equivalent because of the inversion centers lying between each pair of adjacent Ni-II atoms. In the chain, the Ni center dot center dot center dot Ni separations across the end-on and end-to-end azide bridges are 3.236 (4) and 4.975 (4) angstrom, respectively, and the end-on azide bridging Ni-N-Ni angle is 100.8 (2)degrees.