Hydrothermal synthesis, structure and rare ferromagnetic property of a 3-D Nd(III) metal–organic framework based on mixed pyridine-2,5-dicarboxylic acid/nicotinic acid ligands

A novel 3-D metal–organic framework Nd(2,5-pydc)(nic)(H2O) (1, 2,5-pydc = pyridine-2,5-dicarboxylic acid, nic = nicotinic acid) has been hydrothermally synthesized and characterized by elemental analyses, IR, and X-ray single-crystal diffraction. Compound 1 is the first MOF based on mixed 2,5-pydc/nic ligands. The title compound displays an interseting 3-D (6,3)-connected network with the topology of (4.62)2(42 × 610 × 83). Magnetic susceptibility measurements show that compound1 presents a rare ferromagnetic interaction between two adjacent Nd(III) ions.