A novel efficient antenna complex of Eu3+ [Eu(CPFHP)3(DDXPO)] supported by a highly fluorinated carbazole-substituted P-diketonate ligand, namely, 1-(9H-carbazol-2-yl)-4,4,5,5,5-pentafluoro-3-hydroxypent-2-en-1-one (CPFHP) and the 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene oxide (DDXPO) ancillary ligand, has been synthesized, structurally characterized, and its photoluminescent behavior examined. The single-crystal X-ray diffraction analysis of Eu(CPFHP)(3)(DDXPO) revealed that this complex is mononuclear, and that the central Eu3+ ion is surrounded by eight oxygen atoms, six of which are provided by the three bidentate beta-diketonate ligands. The remaining two oxygen atoms are furnished by the chela:ing phosphine oxide ligand. The coordination polyhedron is best described as that of a distorted square antiprism. The photophysical properties of Eu(CPFHP)(3)(DDXPO) benefit from adequate protection of the metal by the ligands with respect to non-radiative deactivation as well as an efficient ligand-to-metal energy transfer process which exceeds 66% in chloroform solution with a quantum yield of 47%. As an integral part of this work, the synthesis, characterize:ion, and luminescent properties of poly(methyl methacrylate) (PMMA) polymer films doped with Eu(CPFHP)(3)(DDXPO) are also reported. The luminescent efficiencies of the doped films (photoluminescence quantum yields 79-84%) are dramatically enhanced in comparison with that of the precursor complex. The new luminescent PMMA-doped Eu(CPFHP)(3)(DDXPO) complex therefore shows considerable promise for polymer light-emitting diode and active polymer optical fiber applications.