Preparation and Properties of Europium

Early in 1827 when Mosander [158] first prepared rare earth metals by the reduction of their chlorides with potassium in a hydrogen atmosphere, the pattern for modem research was actually set. During 1935 Urbain, Weiss, Trombe [159], Klemm and Bommer [160] made significant contributions to this field. 

Fluorides are preferred to chlorides because of the hygroscopic nature of the latter. Daane and Spedding showed that all the rare earth metals except Sm, Eu and Yb can be conveniently prepared by the reduction of their fluorides with calcium. In the case of Sm, Eu and Yb, the trihalides were reduced to dihalides only, no further reduction being acheived. 

Spedding-Hanak-Daane s Method [164] for the Preparation of Metallic 

It has been found that in the preparation of pure europium the starting materials need not be extremely pure. The common impurity viz. samarium is completely eliminated in the above process because samarium is less volatile than europium, and the reduction of Sm2( 3 to the metal requires a higher temperature than the EU2O3 reduction. Commeri-cal lanthanum turnings can also be used for the reduction in place of more expensive very pure lanthanum metal. Extreme care should be taken to ensure that the reactants contain no calcium as it appears as an impurity in the final product if present in the charge. 

Europium is a soft, malleable, grey metal. It is as soft as lead. It is rapidly attacked by moisture at ordinary temperatures and reacts with cold water as fast as does calcium. A pressure of 18,000 psi is required to extrude it into a wire of 1js inch diameter at room temperature. It can be cut with a knife. It has a low tensile strength. It s coefficient of thermal expansion (a) 

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Matijevic, E. and Hsu, W.P., Preparation and properties of monodispersed colloidal particles of lanthanide compounds. 1. Gadolinium, europium, terbium, samarium, cerium(lll), J. Colloid Interf. Sci., 118, 506, 1987. 

Ionic liquid anion nature also has an influence on the properties of Eu-containing luminescent materials [42]. The l-methyl-3-tetradecyl imidazolium ionic liquid with N(CN)2, CF3SO3, and N(CF3S02)2 anions doped with 1 % of [EuCl2Phen2(H20)2] C1DH20 complex was prepared, and the influence of the IL anion nature on luminescent spectra and lifetimes of europium complex was investigated. Therefore the presented Eu-containing ILs can be considered as potential perspective components for new optical materials and devices. 

Lanthanide-doped inverse photonic crystals have been reported.282 The lattices were prepared by infilling self-assembled polystyrene sphere templates with a mixture of zirconium alkoxide and europium at 450 °C, the polystyrene spheres were burnt out leaving hollow spheres of air, and the infilled material was converted to Zr02 Eu3+. The PL properties of the resulting photonic lattice were reported.282 The possibility of including phosphors into photonic lattices could lead to many... 

In spite of the potential basic properties of the Au(CN)2 anion, these complexes were not obtained in an acid-base reaction with silver salts. Instead, they were prepared by slow crystallization of pure gold and silver dicyanide complexes in different molar ratios (x = 0.25, 0.50, 0.75, 0.90). In the case of the two lanthanum derivatives, the exact compositions established by X-ray diffraction studies gave empirical formula in which x = 0.33 and 0.78. For the europium complexes, only one structural determination was performed with x= 0.14. 

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. 

Hurskainen, P., Dahlen, P., Ylikoski, J., Kwiatkowski, M., Siitari, H., and Lovgren, T. (1991) Preparation of europium-labelled DNA probes and their properties. Nucleic Acids Res. 19 1057-1061. 

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