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Three solvent-dependent chiral copper(II) compounds, {[Cu2(bzgluO)2(H2O)2]·4H2O} n ( 1), {[Cu2(bzgluO)2(DMSO)2]·H2O} n ( 2) and [Cu2(bzgluO)2(DMF)2] n ( 3) (H2bzgluO= N-benzoyl- L-glutamic acid) have been synthesized under ambient temperature conditions and characterized by elemental analysis, IR spectra, UV spectra, thermogravimetric analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. Compounds 1 and 2 both crystallize in the orthorhombic space group P212121. Compound 3 crystallizes in the tetragonal space group P43. Compound 1 exhibits a ladder-like 1D chain structure, which is extended by hydrogen-bonding interactions to form a 3D supramolecular network. Compounds 2 and 3 both give a diamond-like 3D structure. Besides, there are hydrogen-bonding interactions in 2. The structural difference indicates that the solvent system plays a crucial role in modulating structures of coordination compounds. Circular dichroism (CD) and the magnetic properties of the compounds have also been investigated. [ABSTRACT FROM AUTHOR]

Sr2CeO4/Ln3+ (Ln = Er, Ho, Tm) phosphors were synthesized with the microwave radiation method for the first time. The luminescent properties of the samples were investigated and the up-conversion luminescence of Er3+, Ho3+ and Tm3+ doped Sr2CeO4 phosphors was observed. The spectra indicate that the energy transfer takes place from the triplet excited state of MLCT (metal-to-ligand charge transfer) state for Sr2CeO4 (sensitizer) to the rare earth ions (activator). [ABSTRACT FROM AUTHOR]

Abstract: Rare earth Eu3+-doped nanoceria powders were prepared by polyvinyl alcohol assisted self-rising synthesis. The X-ray diffraction and Raman spectra data indicate the formation of solid solutions and the existence of oxygen vacancies after Eu3+ doping into the samples. The powders are well-dispersed and the particle size is around 100nm, as can be seen from the scanning electron microscopy. Under the excitation of ultra-violet light 373nm, the nanoceria powders emit weak orange-red light at low Eu3+ doping concentration. However, excited at the same condition, the nanoceria samples generate strong red light at high Eu3+ concentration. The luminescence difference is due to the obvious change of the predominant transition emission. Additionally, the luminescence intensity of the Eu3+-doped nanoceria powders is dramatically enhanced as compared with the same composition samples achieved through simple solution combustion synthesis. The phenomena are beneficial for their potential applications in opto-electronic devices. [Copyright &y& Elsevier]