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Heating of a pink two-dimensional CoIJII) coordination networkbuilt from 1,4-benzenedicarboxylic acid (H 2 bdc) residues and thionicotinamide (S-nia) ligands initiates a single-crystal-to-singlecrystal transition accompanied by removal of both coordinated and co-crystallized solvents. In the dry blue form, [CoIJbdc)IJS-nia)] n (dry_1), the CoIJII) centers changed from an octahedral to a square pyramidal configuration.

A one-dimensional linear coordination polymer {[Cu3(μ3-OH)(2-pyao)3(bdc)]·6(H2O)}n () composed of trinuclear [Cu3(μ3-OH)(2-pyao)3](2+) metallacrown cores bridged by bis-carboxylato linkers has been obtained by treatment of copper(ii) fluoride with pyridine-2-aldoxime (2-pyaoH) ligand and benzene-1,4-dicarboxylic acid (H2bdc). Magnetic susceptibility measurements show strong antiferromagnetic interactions between Cu(ii) centers within the trinuclear metallacrown core with J = -430 cm(-1).

Based on solvothermal synthesis, self-assembly of the heptadentate 2,6-diacetylpyridine bis(nicotinoylhydrazone) Schiff base ligand (H2L) and Zn(II) and/or Cd(II) salts has led to the formation of three homometallic [CdL]n (1), {[CdL]∙0.5dmf∙H2O}n (2) and {[ZnL]∙0.5dmf∙1.5H2O}n (3), as well as two heterometallic {[Zn0.75Cd1.25L2]∙dmf∙0.5H2O}n (4) and {[MnZnL2]∙dmf∙3H2O}n coordination polymers. Compound 1 represents a 1D chain, whereas 2–5 are isostructural and isomorphous two-dimensional structures. The entire series was characterized by IR spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction and emission measurements. 2D coordination polymers accommodate water and dmf molecules in their cage-shaped interlayer spaces, which are released when the samples are heated. Thus, three solvated crystals were degassed at two temperatures and their photoluminescent and adsorption–desorption properties were recorded in order to validate this assumption. Solvent-free samples reveal an increase in volume pore, adsorption specific surface area and photoluminescence with regard to synthesized crystals.

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A new three-dimensional coordination polymer, {[CoIJμ 2 -H 2 O)IJbdc)-IJH 2 O)IJdmf)]•0.5H 2 O} n (1), was obtained as a by-product in the synthe-where H 2 bdc = 1,4-benzenedicarboxylic acid, S-nia = thionicotinamide, dmf = N,N′-dimethylformamide). The threedimensional network in 1 is organized of CoIJII) atoms in O 6 octahedral coordination environments separated by μ 2 -water molecules in coordination chains. The bdc 2− anions coordinate in monodentate mode and also act as bridging ligands that extend the structure in two other directions. The coordination cores of two crystallographically different CoIJII) atoms are completed by either two dmf or two water molecules. The rhombohedral open channels contain water molecules. The evacuation of solvents from 1 occurs as a single crystal to single crystal transformation and results in MOF-71, [CoIJbdc)IJdmf)] n , whose structure was confirmed by single crystal X-ray diffraction.

Enterosorbents are widely-used materials for human body detoxification, which function by immobilizing and eliminating endogenous and exogenous toxins. Here, activated carbons, obtained from the lignocellulosic raw vegetal materials of indigenous provenance, have been studied. Walnut shell and wood from local species of nuts and apple-trees were carbonized, and further activated at high temperatures with water vapors in a rotary kiln. A second activation was carried out, in a fluidized bed reactor, but for shorter times. The textural properties of the samples were determined from the adsorption isotherms of nitrogen at 77 K, allowing the obtaining of highly mesoporous materials, while the adsorption capacity permitted an essential rise of six to seven times in the maximal adsorption values of the metabolites, which was determined by the reactivation process. A kinetic study of vitamin B12 and creatinine immobilization was performed, the optimal immobilization time for the apple-tree wood reactivated carbons being 2 times longer than for those originating from walnut shells. An additional investigation was also performed in specific conditions that simulate the real environment of immobilization: the temperature of a febrile human body (at the temperature T = 38 °C) and the characteristic acidity of the urinary tract and stomach (at the pH of 5.68 and 2.53, respectively). The activated carbonic adsorbents studied here, together with the results of the immobilization studies, show that these procedures can conduct a good incorporation of some endogenous metabolic products, such as vitamin B12 and creatinine, therefore presenting a good opportunity for their use as forthcoming commercial enterosorbents.

The influence of the metal, ligand, and solvent on structures and emission properties was monitored.