We have synthesized a new family of metal-organic-frameworks (MOFs) based on a 9,10-anthracenedicarboxylate linker. We report the formation of lanthanide-based MOFs using soft solvothermal routes with dimethylformamide as a solvent. These materials display intense photoluminescence properties in the solid state at room temperature. What is more interesting is, some of them exhibit slow relaxation of magnetization with activation barriers of 22.9, 15.4, 52.7, 13.0 and 16.2 K for Nd(3+), Gd(3+), Dy(3+), Er(3+) and Yb(3+), respectively. To the best of our knowledge, Nd(3+) and Yb(3+) materials are the first examples of 3D- and 2D-MOFs, respectively, that show slow relaxation of magnetization.

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Three novel metal-organic-frameworks (MOFs) based on dysprosium as the metal and dicarboxylic ligands have been solvothermally synthesized with the aim of studying and modulating their magnetic properties according to the variation of the distances between metal centers. These materials display intense photoluminescence properties in the solid state at room temperature. In addition, a very interesting property of compound 1 is that it exhibits slow relaxation of magnetization with an activation energy barrier of 32 K.Magneto-structural correlations have been analyzed.

The synthesis of a new MOF with Cu2 paddle-wheels connected to glutarate and 1,3-bis(4-pyridyl)propane linkers has been explored. Experimental gas adsorption measurements reveal that the MOF is essentially non-porous to methane whereas it presents a type III isotherm upon CO2 adsorption, leading to high capacity and outstanding CO2 selectivity.

Three new heterometallic metal-organic frameworks, namely, {(PhP)[MnCu(Hmesox)Br(HO)]·HO} (1), {(PhP)[CoCu(Hmesox)Br]} (2) and {(PhP)[ZnCu(Hmesox)Br]·2.5HO} (3) were prepared and their structure and magnetic properties were investigated (Hmesox = mesoxalic acid, PhP = tetraphenylphosphonium). The structure of all the compounds consist of two interpenetrating opposite-chirality supramolecular cationic and polymeric anionic 3-D (10,3)-a networks, which results in chiral compounds. The anionic network is formed from the polymerization of [Cu(Hmesox)Br] units, working as three connectors, and M(ii) cations, working as three-connecting nodes, M = Mn(ii), Co(ii) and Zn(ii). The PhP cations build the cationic chiral supramolecular network opposite to the anionic one. Compounds 1 and 2 exhibit long-range magnetic ordering with critical temperatures of 7.2 K and 6.9 K, respectively. However, compound 3 does not display long-range order, but shows ferromagnetic and antiferromagnetic coupling among the Cu(ii) ions. The magnetic interactions are studied by DFT calculations and compared with related Cu(ii)-mesoxalate compounds previously reported.