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Europium solid compounds

Cyclooctatetraenyl europium and cyclooctatetraenyl ytterbium were isolated as orange or pink solid compounds, after europium or ytterbium, dissolved in liquid ammonia reacted with cyclooctatetraene (Hayes and Thomas, 1969a De Kock et al., 1978) ... [Pg.554]

Americium, unlike europium, does not have a divalent state in aqueous solution this was long greeted with some surprise. However, Am(n) has been prepared in the solid compounds AmQj, AmBr2, and Aml2 and demonstrated as a dilute solution in Cap2 [99-102,105]. Reduction conditions used to prepare Eu and Sm " do not reduce Am (aq) to Am (aq) [229]. Myasoedov et al. claim electrochemical evidence for unstable Am(ii) in acetonitrile, instantly oxidized by water in the solvent [230]. Sullivan et al. [356] formed transient Am(ii) by pulse radiolysis, with an absorption maximum at 313 nm, and tj/2 5 x 10 s for disappearance. [Pg.38]

Cario, L., Lefond, A., Palvadeau, A., Deudon, P., and Meerschault, C. (1999). Evidence of a mixed valence state for europium in the misfit layer compound [(EuS)i.5]i. i5NbS2 by means of a superspace structural determination, Mossbauer spectroscopy and magnetic measurements. /. Solid State Chem. 147, 58-67. [Pg.258]

The lutetium hahdes (except the fluoride), together with the nitrates, perchlorates, and acetates, are soluble in water. The hydroxide oxide, carbonate, oxalate, and phosphate compotmds are insoluble. Lutetium compounds are all colorless in the solid state and in solution. Due to its closed electronic configuration (4f " ), lutetium has no absorption bands and does not emit radiation. For these reasons it does not have any magnetic or optical importance, see also Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Neodymium Praseodymium Promethium Samarium Terbium Ytterbium. [Pg.752]

Solid Europium Compounds. Solid europium oxide, chalcogenides, halides, carbonate, phosphate, etc., may be obtained by reduction of the corresponding Eu3 + compounds or, metathetically, from EuC12. The metal reacts with liquid ammonia at 50° to give the orange amide, Eu(NH2)2, which gives EuN when heated.54 The compounds are usually isostructural with the Sr2 + or Ba2+ analogs. However, definite lower fluorides and chlorides appear to exist except for La, Ce, Pr, Gd, Tb and Er.57... [Pg.1075]

Europium monoxide is the only ionic rare earth monoxide. It is a dark red compound with the NaCl structure, slightly nonstoichiometric, and has semiconducting properties that vary as a function of composition [45]. It has been prepared as slightly nonstoichiometric material EuOi,o2 by reaction of Eu metal with stoichiometric EU2O3 in a sealed tube as a polycrystalline solid [32,46] or (stoichiometry not reported) from a melt as single crystals [45]. When heated it decomposes ... [Pg.173]

Along the EUB6-B4C section again the formation of the solid solution EuBg- Q occurs, but no ternary compound was found. The isothermal section of the tentative phase diagram of the europium-boron-carbon system at 1500°C has been deduced (see fig. 17). To give a better overview, the Eu(B, C)g and i2+xCz-x solid solution has not been included within the diagram. [Pg.117]

The synthesis of europium-doped strontium carbodiimide, SrNCNrEu, was successfully accomplished by the solid-state reaction of Srl2, Eul2 CsCN, and CSN3. The crystal structure and purity of the a polymorph were checked by X-ray diffraction and infrared spectroscopy (Figure 3), and the results closely resemble those already found for the pure strontium compound. In particular, the average M—N bond distance arrives at 2.634(6) A, to be compared with d(Sr—N) = 2.644(4) A from a-SrNCN. ... [Pg.3]

The existence of changes in the crystal structure, probably was not so earth-shaking since the R2O3 compounds were known to have three polymorphic forms in the lanthanide series. But the anomalous densities (or atomic volumes) for europium and ytterbium was an exciting development, since it showed that these two metals were divalent while the remaining lanthanide elements were trivalent. This discovery was one of the first examples verifying Hund s rule (that half-filled and completely filled shells are stable electronic states), which involved a solid-state property other than a magnetic or an optical property measurement. [Pg.411]

Compound 8 (1.0 g, 2.24 mmol) was dissolved in THF (5 mL) in a 15-mL, round-bottomed flask and 1.0 M sodium hydroxide (2.46 mL) was added, dropwise. A solution of europium chloride hexahydrate (0.274 g, 0.75 mmol) in water (2 mL) was added and the flask was equipped with a reflux condenser. The reaction was heated to reflux for 3 h before excess methanol was added to end the reaction. The precipitate was removed by filtration, dried, dissolved in ether, filtered again, and precipitated into hexanes. The precipitate was isolated by filtration, which gave a red solid (750 mg, 66% yield). Anal, (found/calc for C69H54EUF9O9S6) C 53.55 (53.73), H 3.56 (3.53). [Pg.23]


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See also in sourсe #XX -- [ Pg.1075 ]




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Europium

Solid compound

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