Lanthanide Metal-Organic Frameworks Exhibiting Fluoro-Bridged Extended Chains: Synthesis, Crystal Structures, and Magnetic Properties.

Two fluoro-bridged lanthanide-containing metal-organic frameworks (MOFs) were synthesized using 2,2'-bipyridine-4,4'-dicarboxylic acid (BPDC), a fluorinated modulator, and a lanthanide nitrate. The syntheses of MOFs containing Gd 3+ or Tb 3+ and a closely related MOF structure containing Ho 3+ , Gd 3+ , or Tb 3+ are presented. The presence of the fluorinated metal chains in these MOFs is shown through single crystal X-ray diffraction, energy dispersion X-ray spectroscopy, 19 F nuclear magnetic resonance, and X-ray photoelectron spectroscopy. Magnetic measurements reveal weak antiferromagnetic exchange between the Ln 3+ ions mediated by fluoride anions along the zigzag ladder chains present in the crystal structures of these MOFs.