Magnetostructural characterisation of two M–NCO–bpa polymers (M = Co, Mn and bpa = 1,2-bis(4-pyridyl)ethane)

The combination of bpa with the pseudohalide cyanate (NCO−) leads to the preparation of two new isomorphous compounds exhibiting the formula [M(NCO)2(bpa)2]n·bpa where M = Co (1), Mn (2). Both of them have been magnetostructurally characterised by means of X-ray diffraction analysis, TG measurements, IR and ESR spectroscopies and measurements of the magnetic susceptibility. Both compounds consist of M–(gauche-bpa)2–M chains connected through H-bonds. The resulting network shows pseudo-channels (8.5 A × 9.3 A). The structure also exhibits anti-bpa groups performing as crystallisation molecules that are perpendicularly disposed to the pseudo-channels. Both compounds exhibit antiferromagnetic interactions through metallic centres.