Synthesis and Characterization of Three Ytterbium Coordination Polymers Featuring Various Cationic Species and a Luminescence Study of a Terbium Analogue With Open Channels

Four novel metal-organic frameworks with 4,4'-oxybis(benzoate) (OBA) ligands and suitable cationic species, [NH3(CH2)(2)NH3](0.5)[Yb(OBA)(2)(H2O)] (1), (NH4)[Yb(OBA)(2)(H2O)(2)] (2), Na[Yb(OBA)(2)]center dot 0.4DMF center dot 1.5H(2)O (3), and Na[Tb(OBA)(2)]center dot 0,4DMF center dot 1.5H(2)O (4), have been synthesized and structurally characterized. The two-dimensional structure of 1 possesses open channels filled with ethylenediamine cations. The two-dimensional structure of 2 contains the network featuring organic ligands with uncoordinated functional RCO2 groups suspended within the windows. The three-dimensional structure of 3, in which Na+ cations replaced the NH4+ cations of 2 and the presence of DMF molecules, adopts an open framework with large rhombic channels. The evacuated phase Na[Yb(OBA)(2)] in 3 retained rigidity and crystallinity to a high temperature. Framework 4, a terbium analogue of 3, has the potential sensing ability; it exhibited gradually increasing luminescence intensities when dispersed sequentially in water, methanol, and ethanol as suspensions.