Europium ternary complexes

Sun, M., Xin, H., Wang, K.Z., et al. (2003) Bright and monochromic red light-emitting electroluminescence devices based on a new multifunctional europium ternary complex. Chemical Communications, 702-703. Liang, L.S., Zhou, Q.G, Cheng, Y.X., and Wang, L.X. (2003) Oxadiazole-functionalized europium(III) P-diketonate complex for efficient red electroluminescence. Chemistry of Materials, 15, 1935-1937. 

SPECTROFLUORIMETRIC DETERMINATION OF OXYTETRACYCLINE AND CITRATE ION USING TERNARY COMPLEX WITH EUROPIUM(III)... 

Another completely different approach consists in choosing a dye, that already possesses aminocarboxylate functions (Meshkova et al., 1992a), such as triphenylmethane dyes. The latter can be used for selective luminescent determination of Nd111 and Ybm in samarium oxide, for instance. As previously described in the section devoted to /3-diketonates (section 3.2.1), the triplet excited states of /i-dikctonatcs lie at energies >20 000-25 000 cm-1, above most of the accepting levels of Lnm ions. As a consequence, determination of Ndm and Yb111 in europium or samarium oxides is difficult using /3-dike to nates since these two ions exhibit luminescence in the NIR, especially Smm with emission lines at 908, 930, 950, and 1038 nm close to the analytical lines of Ndm and Ybm. Therefore, the detection limit of Ndm and Ybm in samarium compounds by luminescence of their ternary complexes with tta and phen is only 0.1-1 wt%. 

M. Aihara, M. Arai, and T. Taketatsu, Flow Injection Spectrofluorimetric Determination of Europium(III) Based on Solubilizing Its Ternary Complex with Thenoyltrifluoroacetone and Trioctylphosphine Oxide in Micellar Solution. Analyst, 111 (1986) 641. 

M. Fujiwara, S. Tsukahara, and H. Watarai, Time-resolved total internal reflection fluorometry of ternary europium(III) complexes formed at the liquid-liquid interface, Phys. Chem. Chem. Phys., 1, 2949-2951 (1999). 

Because of the preference of trivalent rare-earth ions for 05 gen donor ligands, the interaction between 1,10-phenanthroline and rare-earth ions is very weak in aqueous solution. 1,10-Phenanthroline does not form stable complexes with rare-earth ions in water. However, when 3 equivalents of a j8-diketone with an aromatic substituent (e g. Hdbm, Hbtfa or Htta) are mixed with 1 equivalent of 1,10-phenanthroline and 1 equivalent of Eu " " in aqueous solution, a highly luminescent ternary europium(III) complex is formed (Frey et al., 1994). No ternary complexes were formed in the case of Hacac, Hhfa or Hbzac. These experimental facts point to the existence of a synergistic coordination in ternary complexes of rare-earth ions with jS-diketonate ligands that contain aromatic groups and 1,10-phenanthroline. 

Fig. 5. Highly coordinated ternary complex between europium tris( -diketonate) 6 and two pyridine molecules.

Fu L., Zhang H., Wang S., Meng Q., Yang K. and Ni J. Preparation and luminescence properties of the ternary europium complex incorporated into an inorganic/polymer matrix by a sol-gel method, J. Sol-Gel Set. Technol. 15 (1999) pp. 49-55. 

Figure 3.9 Structures of (a) [CeL3(phen)]2 (HL = acetic acid) and (b) [EnL3(phen)]2 (HL = 2-furancarboxylic acid) [RE, black (large balls) O, grey N, black (small balls) C, white H, omitted]. (Redrawn from the CIF files of A. Panagiotopoulos et al., Molecular structure and magnetic properties of acetato-bridged lanthanide(III) dimers, Inorganic Chemistry, 34, 4918 920, 1995 [37] and X. Li et al., Synthesis, structure and luminescence property of the ternary and quaternary europium complexes with furoic acid, Journal of Molecular Structure, 604, 65-71, 2002 [48].)...

Li, X., Jin, L., Lu, S., and Zhang, J. (2002) Synthesis, structure and luminescence property of the ternary and quaternary europium complexes with furoic acid. Journal of Molecular Structure, 604, 65-71. 

Bian, Z.Q., Gao, D.Q., Guan, M., et al. (2004) Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives. Science in China (Series B), 47, 326-334. 

Complex-formation and redox reactions have so far been the most frequently used for the determination of both metals and nonmetals (Table 3). A variety of transition metal ions have been thus determined including such common elements as iron, copper, and calcium and rare earths as well as technetium and europium. Common nonmetals such as nitrogen anions and phosphate, bromide, and sulfur anions have also been determined this way. However, the most important applications of noncatalytic reactions in inorganic analysis are the simultaneous determinations of metal ions. As can be seen in Table 4, a wide variety of binary mixtures and some ternary and even... 

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