gadolinium

gadolinium
—gadolinic, adj.
/gad'l in"ee euhm/, n. Chem.
a rare-earth metallic element. Symbol: Gd; at. wt.: 157.25; at. no.: 64.
[1885-90; see GADOLINITE, -IUM]

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 (Gd), chemical element, rare-earth metal of the lanthanoid series of the periodic table. Silvery white and moderately ductile, the metal reacts slowly with oxygen and water. Below 17° C it is ferromagnetic and at very low temperatures, superconducting. Credit for the discovery of gadolinium is shared by J.-C.-G. de Marignac (Marignac, Jean-Charles-Galinard de) and P.-É. Lecoq de Boisbaudran (Lecoq de Boisbaudran, Paul-Émile). Marignac separated (1880) a new rare earth (metallic oxide) from the mineral samarskite; Lecoq de Boisbaudran obtained (1886) a fairly pure sample of the same earth, which with Marignac's assent he named gadolinia, after a mineral in which it occurs that in turn had been named for the Finnish chemist Johan Gadolin. Gadolinium occurs in many minerals along with the other rare earths but is obtained primarily from monazite. It is found also in the products of nuclear fission. Commercial separation depends upon ion-exchange techniques. The metal has been produced by thermoreduction of the anhydrous chloride or fluoride by calcium.

      Gadolinium is used for certain electronic components and high-temperature refractories and as an alloying agent. H. Kamerlingh Onnes (Kamerlingh Onnes, Heike) first produced (1923) temperatures below 1 K by magnetic cooling using gadolinium sulfate. Gadolinium has the highest absorption cross section for thermal neutrons of any natural isotope of any element (49,000 barns), which suggests its use in nuclear reactor control rods. The seven natural stable isotopes have mass numbers between 152 and 160; the species of highest mass numbers are more abundant.

      Gadolinium displays the oxidation state +3 in all of its compounds; it behaves as a typical rare earth. Its salts are white, and its solutions are colourless.

atomic number
64
atomic weight
157.250
melting point
1,311° C
boiling point
3,233° C
specific gravity
7.898 (25° C)
oxidation state
+3
electronic config.
[Xe]4f 75d16s2

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Universalium. 2010.

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  • Gadolinium — (pronEng|ˌgædəˈlɪniəm) is a chemical element that has the symbol Gd and atomic number 64. TOC Characteristics Gadolinium is a silvery white, malleable and ductile rare earth metal with a metallic lustre. It crystallizes in hexagonal, close packed …   Wikipedia

  • Gadolinium — Europium ← Gadolinium → Terbium …   Wikipédia en Français

  • gadolinium — [ gadɔlinjɔm ] n. m. • 1886; de gadolinite, silicate, du n. du minéralogiste Gadolin ♦ Chim., phys. Élément chimique (Gd; no at. 64; m. at. 157,2) de la famille des lanthanides. ● gadolinium nom masculin (de Gadolin, nom propre) Métal du groupe… …   Encyclopédie Universelle

  • gadolinium — Symbol: Gd Atomic number: 64 Atomic weight: 157.25 Soft silvery metallic element belonging to the lanthanoids. Seven natural, stable isotopes are known in addition to eleven artificial isotopes. Gd 155 and Gd 157 and the best neutron absorbers of …   Elements of periodic system

  • Gadolinium — Gad o*lin i*um, n. [NL. See {Gadolinite}.] (Chem.) A rare earth metallic element of the Lanthanide series, with a characteristic spectrum, found associated with yttrium and other rare earth elements. Symbol, Gd; it has an atomic number of 64, an… …   The Collaborative International Dictionary of English

  • gadolinium — metallic element, named 1886 by J.C. Marginac in honor of Johan Gadolin (1760–1852), Finnish minerologist and chemist, who in 1794 first began investigation of the earth which eventually yielded the element and several others …   Etymology dictionary

  • gadolinium — [gad΄ō lin′ē əm] n. [ModL, earlier gadolinia: so named (1886) by P. E. L. de Boisbaudran (1838 1912), Fr chemist, and J. C. G. de Marignac (1817 94), Swiss chemist, who had each isolated it, in honor of J. Gadolin (see GADOLINITE) + IUM] a… …   English World dictionary

  • Gadolinium — Eigenschaften …   Deutsch Wikipedia

  • Gadolinium — Ga|do|li|ni|um 〈n.; s; unz.; chem. 〉 zu den Metallen der Lanthanoiden gehörendes Element, Ordnungszahl 64 [nach dem finn. Chemiker J. Gadolin, 1760 1852] * * * Ga|do|li|ni|um [nach dem finnischen Chemiker J. Gadolin (1760–1852); ↑ ium (1)], das;… …   Universal-Lexikon

  • Gadolinium — gadolinis statusas T sritis fizika atitikmenys: angl. gadolinium vok. Gadolinium, n rus. гадолиний, m pranc. gadolinium, m …   Fizikos terminų žodynas

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