Structure and Magnetic Field-Induced Transition in a One-Dimensional Hybrid Inorganic−Organic Chain System, Co<sub>2</sub>(4,4′-bpy)(tfhba)<sub>2</sub>·4,4′-bpy (4,4′-bpy = 4,4′-Bipyridine; tfhba = 2,3,5,6-Tetrafluoro-4-hydroxybenzoate)

Two isostructural hybrid inorganic−organic frameworks, M<sub>2</sub>(4,4′-bpy)(tfhba)<sub>2</sub>·4,4′-bpy, (M = Co (<b>1</b>), Zn (<b>2</b>); 4,4′-bpy = 4,4′-bipyridine; tfhba = 2,3,5,6-tetrafluoro-4-hydroxybenzoate) have been synthesized and their structures elucidated using single crystal X-ray diffraction. These materials are the first hybrid structures synthesized using the tfhba ligand. They contain a one-dimensional chain of corner-sharing MO<sub>4</sub>N trigonal bipyramids that has not been observed to date for Co<sup>2+</sup> units. The magnetic properties of <b>1</b> have been investigated and indicate ferromagnetic ordering along the chains, with weak antiferromagnetic interactions between them. Overall the system is antiferromagnetic with a Néel temperature of 3 K, but undergoes a field-induced magnetic phase transition at 3 kOe.