Two cobalt(II) coordination polymers, {[Co(µ-4,4Јbipy)(4,4Ј-bipy) 2 (H 2 O) 2 ]·(OH) 3 ·(Me 4 N)·4,4Ј-bipy·4H 2 O} n (1) and {[Co(µ-4,4Ј-bipy)(H 2 O) 4 ]·suc·4H 2 O} n (2) (4,4Ј-bipy ϭ 4,4Ј-bipyridine, suc ϭ succinate dianions), were hydrothermally synthesized and structurally characterized by X-ray diffraction analysis, UV-Vis-NIR, and ICP. The main structure feature common to the both polymers is presence of the infinite linear chains, [Co(µ-4,4Јbipy)(4,4Ј-bipy) 2 (H 2 O) 2 ] n (1) and [Co(µ-4,4Ј-bipy)(H 2 O) 4 ] n (2), respectively. In 1, the chains are further linked by the hydrogenbond and π-π stacking interaction, producing extended layer structure. The 4,4Ј-bipy molecules in 1 play three different roles. In 2,

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Three cadmium(II) coordination polymers [Cd(NA) 2 -(H 2 O) 2 ] n (1), {[Cd(NA)(phen)(NO 3 )]·(H 2 O) 1/2 } n (2), {[Cd(NA)-(CH 3 C 6 H 4 COO)(H 2 O) 2 ]·(CH 3 C 6 H 4 COOH)} n (3) (HNA ϭ nicotinic acid, phen ϭ 1, 10-phenanthroline) have been synthesized by hydrothermal method. Their single-crystal structures were determined by X-ray diffractometry. The absorption, excitation and emission spectra were investigated and all the complexes emit strong fluorescence: λ em max ϭ 544 nm (λ ex ϭ 492 nm), 1; λ em max ϭ 466 nm (λ ex ϭ 393 nm), 2; λ em max ϭ 430 nm (λ ex ϭ 313 nm), 3. At room temperature in the solid state the fluorescence lifetimes of the complexes were investigated and the relationships between the spectra were discussed as well as the connections of luminescence and crystal structures.

A series of lanthanide-transition metal (Ln-M) complexes, namely, {[Ln 2 Cu(pydc) 4 (H 2 O) 3 ]ÁH 2 O} n (Ln = Tb, Eu, Sm or Gd) (H 2 pydc = 2,5-pyridinedicarboxylic acid) have been synthesized hydrothermally by selfassembly of the lanthanide ions, copper(II) ions and 2,5-pyridinedicarboxylic acid. All the complexes were characterized by physicochemical and spectroscopic methods; in addition, structural analyses revealed that all four complexes crystallized in monoclinic space group P2 1 /c. The molecular structure contains both Cu and Ln atoms, with pydc ligands bridging the four coordinate Cu(II) centers and eight coordinate lanthanide centers to form a 3-D net structure. Hence, copper is oxidized from Cu(I) to Cu(II) during the preparation. In addition, the thermogravimetric analysis of 1 is discussed. Contrary to expectations, compounds 1-3 show no photoluminescent properties.

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