Neutron Diffraction Studies of the Molecular Compound [Co<sub>2</sub>(bta)]<sub><i>n</i></sub> (H<sub>4</sub>bta =1,2,4,5-Benzenetetracarboxylic Acid): In the Quest of Canted Ferromagnetism FabeloOscar Cañadillas-DelgadoLaura PasánJorge Díaz-GallifaPau Ruiz-PérezCatalina LloretFrancesc JulveMiguel Puente OrenchInés CampoJavier Rodríguez-CarvajalJuan 2013 The exchange mechanism and magnetic structure of the organic–inorganic layered molecule-based magnet [Co<sub>2</sub>(bta)]<sub><i>n</i></sub> (<b>1</b>) (H<sub>4</sub>bta =1,2,4,5-benzenetetracarboxylic acid) have been investigated through variable-temperature magnetic susceptibility measurements and supported with a series of neutron diffraction experiments. Cryomagnetic studies have shown an antiferromagnetic ordering at a transition temperature of 16 K that is followed by the appearance of a weak ferromagnetism below 11 K. The weak antiferromagnetic interlayer interaction plays an important role in this system in spite of the long interlayer separation. A ferromagnetic ordering is induced by applied magnetic fields greater than 1800 G (metamagnetic behavior), and a slow magnetic relaxation from this ferromagnetic phase to the antiferromagnetic one is observed. The magnetic structure of <b>1</b> has been elucidated at low temperatures in zero field by neutron powder diffraction measurements and was found to be of antiferromagnetic nature with the local cobalt­(II) spins (magnetic moments) being aligned ferromagnetically in the <i>ac</i> plane and antiferromagnetically coupled along the crystallographic <i>b</i> axis. No evidence for a long-range spontaneous ferromagnetic component below 11 K was observed in the neutron experiment.