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

Abstract

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 Xray 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.

Linker installation transformations in a 2-D rare earth MOF: increase of the dimensionality and turn on of the temperature sensing capability

“…This is because UiO-66 exhibits significant thermal, chemical and hydrolytic stability. 17 One of the RE 3+ ions, have attracted attention because of their increased thermal/chemical/hydrolytic stability and their interesting photoluminescence 21 and magnetic 22 properties. Our group is active in this field and we recently reported a family of 8-connected 2-D MOFs based on a hexanuclear SBU and 4,4 0 -sulfonyldibenzoic acid (H 2 SDBA) ligand with capability to selectively detect gases of selected volatile and nitroaromatic organic compounds.…”

“…17 One of the research goals in this area involved the synthesis of analogous compounds based on a hexanuclear SBU with different metal ions, which led to a series of RE 3+ , 18 Ce 4+ , 19 U 4+ 20 and Th 4+ 19,20 MOFs. Among them, MOFs based on polynuclear SBUs with RE 3+ ions, have attracted attention because of their increased thermal/chemical/hydrolytic stability and their interesting photoluminescence 21 and magnetic 22 properties. Our group is active in this field and we recently reported a family of 8-connected 2-D MOFs based on a hexanuclear SBU and 4,4′-sulfonyldibenzoic acid (H 2 SDBA) ligand with capability to selectively detect gases of selected volatile and nitroaromatic organic compounds.…”