Cobalt(II) metamagnet built from ferromagnetic chains with mixed bis(azido)(carboxylate) bridges

A new one-dimensional Co(II) coordination polymer, Co(L)(N3)2 (L = pyridinio-N-acetate), has been synthesized by a diffusion method and characterized by single crystal X-ray diffraction. In the compound, Co(II) ions are linked by mixed triple bridges (two end-on azides and a syn–syn carboxylate), which transmit ferromagnetic coupling with J = 13.96 cm− 1. The compound exhibits field-induced metamagnetic behaviors below TN = 2.3 K with Hc = 100 Oe, due to weak antiferromagnetic interactions between chains.