neodymium

neodymium (nē'ōdĭm`ēəm), metallic chemical element; symbol Nd; at. no. 60; at. wt. 144.24; m.p. about 1,021°C;; b.p. about 3,068°C;; sp. gr. 7.004 at 20°C;; valence +3. Neodymium is a lustrous silver-yellow metal. It is one of the rare-earth metals in the lanthanide series of Group 3 of the periodic table. It exists in two distinct forms (see allotropy); at room temperature it has a hexagonal crystalline structure, but when heated above about 800°C; it assumes a face-centered cubic conformation with specific gravity about 6.8. The metal tarnishes in air; the coating formed does not protect the metal from further oxidation, so it must be stored away from contact with air. The oxide (neodymia, Nd₂O₃) is light blue. The metal is also attacked by water and by acids. Its salts form various red aqueous solutions. Neodymium is present in the minerals monazite and bastnasite. The metal may be prepared from its halides by reduction. Neodymium is one of several metals in an alloy commonly used in cigarette lighter flints. Neodymium is used in coloring glasses. The earth didymia is a mixture of the oxides of neodymium and praseodymium. The lenses of goggles used by glassblowers are made with a didymium glass that absorbs the yellow sodium glare of the flame. Neodymium was discovered in 1885 by C. A. von Welsbach who separated Mosander's "didymium" into two components, the earths neodymia and praseodymia.

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neodymium

Metallic chemical element, chemical symbol Nd, atomic number 60. Silvery white in colour, it is a rare earth metal and one of the lanthanide series. It is a component of important alloys, among them misch metal (15% neodymium), used in lighter flints and various metallurgical processes. Alloyed with iron and boron, neodymium is the basis for powerful permanent magnets used in computer hard drives, lightweight earphones, and numerous other applications. Neodymium compounds are employed as ceramics glazes. The crude oxide counteracts the greenish cast imparted to glass by iron contaminants, and a very pure oxide is used to make a vivid purple glass. Neodymium is added to glass or other host materials to form the active elements for certain solid-state lasers. Glass containing a mixture of neodymium and praseodymium (another rare earth element) is used in glassblowers' goggles.

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neodymium

a toxic silvery-white metallic element of the lanthanide series, occurring principally in monazite: used in colouring glass. Symbol: Nd; atomic no.: 60; atomic wt.: 144.24; valency: 3; relative density: 6.80 and 7.00 (depending on allotrope); melting pt.: 1024?C; boiling pt.: 3127?C

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neodymium [‚nē·ō′dim·ē·əm]

(chemistry)

A metallic element, symbol Nd, with atomic weight 144.24, atomic number 60; a member of the rare-earth group of elements.