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With the coordination of dimethylformamide (DMF), two new uranium(VI) complexes with either 4-hydroxybenzoic acid (H 2 phb) or terephthalic acid (H 2 tph) have been synthesized under solvothermal conditions and structurally characterized. [(UO 2 ) 2 (Hphb) 2 (phb)(DMF)(H 2 O) 3 ]·4H 2 O ( 1 ) has a dinuclear structure constructed with both pentagonal and hexagonal bipyramidal uranium polyhedra linked through a µ 2 -bridging ligand via both chelating carboxylate arm and alcohol oxygen bonding, first observation of such a coordination mode of 4-hydroxybenzoate for 5 f ions. [(UO 2 )(tph)(DMF)] ( 2 ) has a three-dimensional (3D) framework built with pentagonal bipyramidal uranium polyhedra linked with µ 4 -terephthalate ligands. The 3D channeled structure is facilitated by the unique carboxylate bonding with nearly linear C–O–U angles and the coordination of DMF molecules. The presence of phb ligands in different coordination modes, uranyl ions in diverse environments and DMF in complex 1 , and tph ligand, DMF and uranyl ion in complex 2 has been confirmed by Raman spectroscopy. In addition, their thermal stability and photoluminescence properties have been investigated. [ABSTRACT FROM AUTHOR]

Four dysprosium (Dy) single carboxylates, a formate, a propionate, a butyrate and an oxalate have been synthesized and structurally characterized. The structure of Dy(HCO 2 ) 3 ( 1 ) contains nine-fold coordinated Dy polyhedra in perfect tricapped trigonal prisms. They are linked through trigonal O atoms forming 1D pillars which are further linked together through tricapped O atoms into a 3D pillared metal organic framework. The network structure is stable up to 360 °C. The structure of [Dy 2 (C 2 O 4 ) 3 (H 2 O) 6 ]·2.5H 2 O ( 2 ) contains nine-fold coordinated Dy polyhedra linking together through μ 2 -bridging oxalate anions into a 2D hexagonal layered structure. Both [Dy 2 (Pr) 6 (H 2 O) 4 ]·(HPr) 0.5 ( 3 ) [Pr=(C 2 H 5 CO 2 ) −1 ] and [Dy 2 (Bu) 6 (H 2 O) 4 ] ( 4 ) [Bu=(C 3 H 7 CO 2 ) −1 ] have similar di-nuclear structures. The Raman vibration modes of the complexes have been investigated. [ABSTRACT FROM AUTHOR]