Facile synthesis of high purity anhydrous complex rare earth halides by the modified mixed-salt-dehydration method

A novel and facile method to produce high purity anhydrous complex rare earth halides was introduced.

Two-Dimensional Coordination Polymers in Rubidium and Caesium Complexes with Orthanilic Acid

The crystal structures of the rubidium and caesium complexes with 2-aminobenzenesulfonic acid (orthanilic acid), [Rb4(C6H6NO3S)4(H2O)]n(1) and [Cs(C6H6NO3S)]n(2), have been determined at 200 K. Complex 1 has a repeating unit comprising four independent and different Rb coordination centres, (RbO8), (RbO7), (RbN2O4) and (RbO10), each having irregular stereochemistry and involving several bidentate chelate sulfonate-O,O′-metal and bridging interactions, giving a two-dimensional polymeric layered structure. Anhydrous complex 2 is also polymeric with the irregular (CsO7) coordination polyhedron comprising six sulfonate oxygen donors from three separate bidentate chelate sulfonate ligands and one monodentate bridging sulfonate oxygen, giving a two-dimensional layered structure.

Preparation, Characterization and Thermal Behavior of Copper(II) Complex with 1-(6-Hydroxynaphthalen-2-Yl)butane-1,3-Dione

A complex of Cu(II) with 1-(6-hydroxynaphthalen-2-yl) butane-1,3-dione (HNBD) was synthesized and characterized by elemental analysis, IR, UV and TG-DTA techniques. IR spectra as well as UV-visible absorption measurements indicated that Cu(II) ion was coordinated to the HNBD ligand. The TG-DTA curves showed that the thermal decomposition for Cu(II) complex was a three-steps process. At first, the complex had a mass loss of water molecules at temperature below 134°C, then the thermal decomposition of the anhydrous complex was a two-stage process, which corresponded to the loss of two naphthol molecules and the oxidative decomposition of other organic fragments of ligand. The final decomposition product of the complex was CuO.

Structural, Magnetic and Mössbauer Studies of Bis(2,6-bis(pyrazol-3-yl)pyridine)iron(II) Triflate and its Hydrates

The electronic properties of bis(2,6-bis(pyrazol-3-yl)pyridine)iron(II) triflate depend markedly on the extent of hydration. The trihydrate is low spin while the monohydrate is high spin at room temperature but undergoes a discontinuous transition to low spin at low temperatures. In the anhydrous complex magnetic and Mössbauer spectral data indicate that there is a minor fraction of low-spin species at room temperature and this fraction increases at low temperatures. The spin transition in the anhydrous salt is continuous and incomplete at 80 K. The structure of the trihydrate reveals an extensive hydrogen-bonding network which involves the uncoordinated >NH groups of the pyrazolyl groups in the ligands, the water molecules and the anions. The disruption of this network on loss of water is believed to be responsible for the change in electronic properties. Bis(2,6-bis(pyrazol-3-yl)pyridine)iron(II) triflate trihydrate: triclinic, space group P-1, a 11·490(5), b 12·218(6), c 13·666(6) Å, α 104 ·67(2), β 104·58(2), γ 104·35(2)°, Z 2.