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New outstanding possibilities are emerging by the synthesis of organo-inorganic polymeric materials from a buildingblock approach. Our approach has been to assemble extended solids from bent flexible arenedicarboxylate linkers that offer totally new topologies with helical channels. A new family of Rare-earth Polymeric Framework (RPF-4) has been obtained and its structure solved. The framework is formed by a Lanthanide (Ln) matrix, with the Ln atoms well separated in two directions. The crystals are highly stable in air and the decomposition temperature is above 350°C. Under UV excitation, the linker presents a bluish-white emission peaking around 450 nm. The emission corresponding to the different crystals either present an emission similar to the linker, slightly modified depending on R, or an intense emission due to Ln localized crystal field transitions. In the second case, an energy transfer from the linker to the Ln ions, which relax radiatively with a very efficient emission, seems to occur. The observed emission properties and crystal stability are of interest for applications as light emitting materials. The peculiarities of the structure may avoid the concentration quenching of the luminescence since Ln ions form well separated chains along a-axis with interchain distances around 12.5 Å.