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Abstract: Reported herein is the synthesis and characterization of luminescent materials containing a Eu(III) complex ((Eu2N,N'- bis[5-{4- vinylbenzyloxy}salicylideneethylenediamine])(3).2H(2)O, 1) immobilized within porous organic hosts using styrene groups for covalent linkages. Porous materials were prepared using template copolymerization methods to afford P-EGDMA-1, having a poly(methacrylate) host and p(DVB)-1, which has a poly(divinylbenzene) host. A DMF solution of 1 displays a strong luminescent signal at lambda(ex) = 610 nm; nearly identical emission spectra are obtained for suspension of P- EGDMA-1 and P-DVB-l in DMF. A large Stokes shift is seen between the excitation (lambda(ex) = 370 nm) and emission wavelengths, eliminating interference from the excitation source. Quenching is observed when organic solvents are introduced into DMF suspensions of the polymers and the effect is proportional to the amount of solvent present. This quenching effect is reversible with the emission signals of P- EGDMA-1 and P-DVB-1 being regenerated upon removal of the quenching molecule. Composition of the organic host is important in modulating the response and sensitivity of these materials to solvent binding. Highly aromatic porous hosts (P- DVB-l) show a greater luminescent response, as well as higher sensitivity toward aromatic compounds (i.e., benzene and toluene), when compared to that of a nonaromatic polymer (P- EGDMA-1). Nonaromatic compounds (methylene chloride) quench the emission signal linearly, but the sensitivity is not significantly different between hosts. These results show that changing the secondary coordination environment is a useful method for tuning selectivity of luminescent materials. This approach demonstrates the utility in preparing metal ion based luminescent materials for chemical detection