Syntheses, topological structures and physical properties of two 2D lanthanide–organic frameworks constructed from 5-nitroisophthalic acid

Two lanthanide–organic frameworks Pr2[(NIPH)3·3H2O]·H2O (1) and [Nd2(NIPH)3·3H2O]·H2O (2) were synthesized via the self-assembly of Ln(NO3)·6H2O (Ln = Pr or Nd) with 5-nitroisophthalic acid (H2NIPH) in the presence of imidazole under hydrothermal reactions. X-ray single-crystal diffraction analyses reveal that 1 and 2 are isomorphic and both exhibit an unprecedented 2D topological net. Compounds 1 and 2 both have a 3D supramolecular framework extended by hydrogen-bonding interactions between the adjacent layers. Furthermore, the magnetic behaviors for 1 and 2 in the temperature range of 2–300 K were investigated.