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Dysprosium oxidation states

Dysprosium has an oxidation state of +3, which forms the Dy metallic ion that is hmited to a small group of compounds. A general example that demonstrates how the ion of dysprosium combines with halogen anions follows Dy + 3C1 — DyCl. ... [Pg.295]

The most common raw materials for the REM molten salt electrolysis are in the RE " state, such as RE2O3, RECI3. But RE " still exists to a certain extent in the molten salts, especially in the chloride melts, some rare earth metal elements have presented a higher level of divalent oxidation states, such as neodymium, samarium, europium, dysprosium, thulium, and ytterbium, which result in a lower current efficiency. For Sm and Eu molten salt electrolysis processes, even no metals can be obtained at the cathodes due to a cyclic transformation of Sm VSm (Eu /Eu ) and Sm /Sm (Eu /Eu ) on the electrodes during electrolysis. And some of the rare earth metal elements show tetravalent oxidation states at the chlorine pressure far in excess of atmospheric pressure, such as Ce. Most of the rare earth metal elements in oxidation state of -1-4 are not stable in chloride melts, because the reaction occurs according to the following equation RE " -I- Cl = RE -" -I- I/2CI2. [Pg.1766]

For ninety years samarium, europium, and 5dterbium were the only accessible divalent rare earths in molecular organometalhc chemistry. However, the past two decades have witnessed the addition of scandium(II), yttrium(II), lanthanum(II), cerium(II), neodymium(II), dysprosium(II), hohnium(II), erbium(n) and thulium(II) in a molecular context.Thus 12 of the 17 rare earths are now known in the divalent state in an organometalhc context and no other area of chemistry has seen such a dramatic expansion in the number of available oxidation states. It would therefore seem to be only a matter of time before divalent states are extended to the remaining REs. An extensive palate of... [Pg.98]

Halides of the lanthanides in the oxidation state -1-2 have been known since the early decades of the twentieth century. EuCl2, SmCl2, and YbCb were the first to be reported. For these 3 elements, ah 12 possible halides are known. This is not the case for the elements thulium, dysprosium, and neodymium for which only the halides of the fiiad chlorine, bromine, and iodine have been synthesized and crystallographically characterized. They structmaUy bear close resemblance to the respective alkahne-earth metal halides. The electronic configmations of the M + ions of these six elements are 6s 5d 4f with n = 4 (Nd), 6 (Sm), 7 (Eu), 10 (Dy), 13 (Tm), and 14 (Yb). [Pg.161]

Paris by the French scientist Paul-Emile Lecoq de Boisbaudran. Its isolation was made possible by the development of ion-exchange separation in the 1950s. Dysprosium belongs to a series of elements called rare earths, lanthanides, or 4f elements. The occurrence of dysprosium is low 4.5 ppm (parts per million), that is, 4.5 grams per metric ton in Earth s crust, and 2 x 10 7 ppm in seawater. Two minerals that contain many of the rare earth elements (including dysprosium) are commercially important mon-azite (found in Australia, Brazil, India, Malaysia, and South Africa) and bast-nasite (found in China and the United States). As a metal, dysprosium is reactive and yields easily oxides or salts of its triply oxidized form (Dy3+ ion). [Pg.30]

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]

Few lanthanide elements may be oxidized to the tetravalent state and stabilized, almost exclusively, in fluorides and oxides. These are the elements cerium, terbium, praseodymium, dysprosium, neodymium, holmium, for example all in the ternary fluorides CS3RF7 (Hoppe and Roedder 1961). There are also hints at pentavalent praseodymium, CsPrFe would be the example (Hoppe 1980). [Pg.55]

In Chapters I and 2, an introduction is made to the synchrotron Mossbauer spectroscopy with examples. Examples include the/ns/tu Mossbauer spectroscopy with synchrotron radiation on thin films and the study of deep-earth minerals. Investigations of in-beam Mossbauer spectroscopy using a Mn beam at the RIKEN RIBF is presented in Chapter 3. This chapter demonstrates innovative experimental setup for online Mossbauer spectroscopy using the thermal neutron capture reaction, Fe (n, y) Fe. The Mossbauer spectroscopy of radionuclides is described in Chapters 4-7. Chapter 4 gives full description of the latest analysis results of lanthanides Eu and Gd) Mossbauer structure and powder X-ray diffraction (XRD) lattice parameter (oq) data of defect fluorite (DF) oxides with the new defect crystal chemistry (DCC) Oq model. Chapter 5 reviews the Np Mossbauer and magnetic study of neptunyl(+l) complexes, while Chapter 6 describes the Mossbauer spectroscopy of organic complexes of europium and dysprosium. Mossbauer spectroscopy is presented in Chapter 7. There are three chapters on spin-state switching/spin-crossover phenomena (Chapter 8-10). Examples in these chapters are mainly on iron compounds, such as iron(lll) porphyrins. The use of Mossbauer spectroscopy of physical properties of Sn(ll) is discussed in Chapter I I. [Pg.652]

Basler, D.B., 1972, High Temperature Oxidation of Gadolinium and Dysprosium Under Controlled Oxygen Partial Pressure, Ph.D. Thesis, Iowa State University, Ames, Iowa. [Pg.394]


See other pages where Dysprosium oxidation states is mentioned: [Pg.1]    [Pg.261]    [Pg.410]    [Pg.308]    [Pg.1058]    [Pg.33]    [Pg.239]    [Pg.218]    [Pg.16]    [Pg.37]    [Pg.86]    [Pg.152]    [Pg.395]    [Pg.367]    [Pg.131]    [Pg.66]    [Pg.443]    [Pg.713]    [Pg.15]    [Pg.703]    [Pg.241]    [Pg.336]    [Pg.709]    [Pg.8]    [Pg.156]   
See also in sourсe #XX -- [ Pg.1244 ]




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