Synthesis, structure and adsorption properties of lanthanide-organic frameworks with pyridine-3,5-bis(phenyl-4-carboxylate).

Under solvothermal conditions, reactions of pyridine-3,5-bis(phenyl-4-carboxylic acid) (H2L) with lanthanide metal salts give rise to three new metal-organic frameworks (MOFs) with the formula {[Ln(4)(L)(3)(mu(3)-OH)(4)(H2O)(4)]center dot(NO3)(2)center dot solvent}(n) [Ln = Er (1), Yb (2) and Lu (3)]. The complexes were characterized by single crystal and powder X-ray diffraction, IR and thermogravimetric analyses. They have the same twofold interpenetrating three-dimensional (3D) framework structures with [Ln(4)(COO)(6)(mu(3)-OH)(4)(H2O)(4)] clusters as secondary building units (SBUs) and a rare 6-connected lcy topology with the point (Schlafli) symbol of {3(3).5(9).6(3)}. Interestingly, 1-3 show selective and hysteretic sorption of CO2 over N-2, and the photoluminescence properties of the complexes were also investigated.