In this paper we report the synthesis and X-ray characterization of four novel hybrid inorganic-organic assemblies generated from H4SiW12O40 as Keggin-type polyoxometalates (POM) and, in three of them, a trinuclear lanthanide cluster of type {Na(H2O)3[Ln(HCAM)(H2O)3]3}(4+) is formed, where Ln metal is La in compound 1, Ce in compound 2, and Eu in compound 3 (H3CAM = chelidamic acid or 2,6-dicarboxy-4-hydroxypyridine). These compounds represent the first POM-based inorganic-organic assemblies using chelidamic acid as an organic ligand. The thermal stability of the organic ligand is crucial, since pyridine-2,6-bis(monothiocarboxylate) instead of chelidamic acid is used (compound 4) under the same synthesis conditions, the decomposition of the ligand to pyridine was observed leading to the formation of colorless crystals of a pseudo hybrid inorganic-organic assembly. In compound 4 the hybrid inorganic-organic assembly is not formed and the organic part simply consists of four molecules of protonated pyridine acting as counterions of the [SiW12O40](4-) counterpart. The luminescent properties of compounds and have been investigated and their solid state architectures have been analyzed. Whereas compound only shows ligand emission, the Eu(3+) emission in compound 3 is discussed in detail. We have found that unprecedented anion-π interactions between the POM, which is a tetra-anion, and the aromatic rings play a crucial role in the crystal packing formation. To the best of our knowledge, this is the first report that describes and analyzes this interaction in Keggin-type POM based inorganic-organic frameworks. The energetic features of these interactions in the solid state have been analyzed using DFT calculations in some model systems predicted by us.

Water clusters", group of water molecules held together by hydrogen bonds, have been the subject of a number of intense experimental and theoretical investigations because of their importance in understanding cloud and ice formation, solution chemistry, and a large number of biochemical processes. "Water clusters" can play an important role in the stabilization of supramolecular systems both in solution and in the solid state and there is clearly a need for chemists a better understanding of how such aggregates influence the overall structure of their surroundings. The present brief review deals with (H 2 O) n clusters, identified/observed crystallographically upon 170 crystal structures of synthesized coordination compounds based upon proton transfer compounds by Hossein Aghabozorg's research groups since 2000. The structural details of water clusters, (H 2 O) n , n = 2, 3,4,5,6,7,8,9,15,16 and are described systematically.

(His.)ZnCl4 nanocatalyst is realized for the preparation of chromenes with a green LED. ˙O2−, OH˙ and h+ are reactive species for this reaction. Complementary tests assured good stability and reusability of the nanophotocatalyst.

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The Fischer–Tropsch synthesis using cobalt catalysts supported on zeolitic imidazolate frameworks (ZIFs), ZIF‐7 and ZIF‐8, has been investigated. ZIF‐7, ZIF‐8 and corresponding cobalt‐containing catalysts, after preparation, were characterized using various techniques. Thermogravimetric analysis results show that ZIF‐7 and ZIF‐8 supports have good thermal stability for the Fischer–Tropsch synthesis reaction, and weaker interaction between cobalt and zinc in the ZIF‐7 and ZIF‐8 supports results in more cobalt reduction. The catalytic performance was evaluated in Fischer–Tropsch synthesis and compared with that of a cobalt catalyst supported on SBA‐15 promoted with zinc. The pore structure of the ZIF supports plays an essential role in product selectivity for the prepared catalysts. The carbon number in hydrocarbon products and olefin selectivity depend on cobalt dispersion and support structure owing to the impacts of site density and carrier skeleton on the speed of diffusion‐enhanced olefin re‐adsorption reactions.