Neodymium

2009-09-02T17:09:30Z

Python9:

{{infobox neodymium}}
'''Neodymium''' ({{pron-en|ˌniː.ɵˈdɪmiəm}}) is a [[chemical element]] with the symbol '''Nd''' and [[atomic number]] 60. It is a soft silvery metal which tarnishes in air. Neodymium was discovered in 1885. It is not found in nature in pure form; its various compounds are present in trace amounts in minerals [[monazite]] and [[bastnäsite]]. Neodymium has several important applications: it is a constituent of [[neodymium magnets]], which are widely used in motors, loudspeakers and numerous appliances. Neodymium is a popular additive in glass, giving it a characteristic reddish-purple color; this glass is used in [[lasers]] emitting [[infrared]] light with the [[wavelength]] of 1.054-1.062 [[micrometers]]. Neodymium is also used in Nd:YAG lasers to generate 1.064 micrometer light. This is one of the most significant solid state lasers. Neodymium is a key component of an alloy used to make high-power lightweight [[neodymium magnet|magnets]] for [[electric motors]] of [[hybrid cars]], and in generators for [[wind turbines]].<ref>[http://www.reuters.com/article/newsOne/idUSTRE57U02B20090831 Steve Gorman, ''As hybrid cars gobble rare metals, shortage looms,'' Reuters, Mon Aug 31, 2009]</ref>

== Characteristics ==
===Physical===
Neodymium, a [[rare earth element|rare earth]] [[metal]], is present in [[mischmetal]] to the extent of about 18%. The metal has a bright, silvery metallic luster; however, as one of the more reactive rare earth ([[lanthanide]]) metals, it quickly oxidizes in air. The oxide layer then falls off, which exposes the metal to further oxidation. Thus a centimeter-sized Nd sample completely oxidizes within a year.<ref>{{cite web|url=http://www.elementsales.com/re_exp/index.htm |title = Rare-Earth Metal Long Term Air Exposure Test|accessdate=2009-08-08}}</ref>

Neodymium exists in two allotropic forms, with a transformation from a double hexagonal to a [[body-centered cubic]] structure taking place at 863 °C.<ref name=CRC>{{cite book| author = C. R. Hammond |title = The Elements, in Handbook of Chemistry and Physics 81th edition| publisher =CRC press| year = 2000| isbn = 0849304814}}</ref>

===Chemical===
Neodymium metal tarnishes slowly in air and burns readily at 150 [[Celsius|°C]] to form [[neodymium(III) oxide]]:
:4 Nd + 3 O2 → 2 Nd2O3

Neodymium is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form neodymium hydroxide:
:2 Nd (s) + 6 H2O (g) → 2 Nd(OH)3 (aq) + 3 H2 (g)

Neodymium metal reacts with all the halogens:
:2 Nd (s) + 3 F2 (g) → 2 NdF3 (s) [violet]
:2 Nd (s) + 3 Cl2 (g) → 2 NdCl3 (s) [mauve]
:2 Nd (s) + 3 Br2 (g) → 2 NdBr3 (s) [violet]
:2 Nd (s) + 3 I2 (g) → 2 NdI3 (s) [green]

Neodymium dissolves readily in dilute [[sulphuric acid]] to form solutions containing the lilac Nd(III) ions, which exist as a [Nd(OH2)9]3+ complexes:<ref>{{cite web| url =https://www.webelements.com/neodymium/chemistry.html| title =Chemical reactions of Neodymium| publisher=Webelements| accessdate=2009-06-06}}</ref>

:2 Nd (s) + 3 H2SO4 (aq) → 2 Nd3+ (aq) + 3 SO{{su|b=4|p=2−}} (aq) + 3 H2 (g)

===Compounds===
{{see also|Category:Neodymium compounds}}
Neodymium compounds include

*Halides: [[neodymium(III) fluoride|NdF3]], [[neodymium(III) chloride|NdCl3]], [[neodymium(III) bromide|NdBr3]], [[neodymium(III) iodide|NdI3]]
*Oxides: [[neodymium(III) oxide|Nd2O3]]
*Sulfides: [[neodymium(II) sulfide|NdS]], [[neodymium(III) sulfide|Nd2S3]]
*Nitrides: [[neodymium(III) nitride|NdN]]

===Isotopes===
{{main|Isotopes of neodymium}}
Naturally occurring neodymium is composed of 5 stable [[isotope]]s, 142Nd, 143Nd, 145Nd, 146Nd and 148Nd, with 142Nd being the most abundant (27.2% [[natural abundance]]), and 2 [[radioisotope]]s, 144Nd and 150Nd. In all, 31 radioisotopes of Neodymium have been characterized up to now, with the most stable being naturally occurring isotopes 144Nd ([[alpha decay]], a [[half-life]] (T½) of 2.29×1015 years) and 150Nd ([[double beta decay]], T½ of 7×1018 years). All of the remaining [[radioactive]] isotopes have half-lives that are less than 11 days, and the majority of these have half-lives that are less than 70 seconds. This element also has 13 known [[meta state]]s with the most stable being 139''m''Nd (T½ 5.5 hours), 135''m''Nd (T½ 5.5 minutes) and 133''m''1Nd (T½ ~70 seconds).

The primary [[decay mode]]s before the most abundant stable isotope, 142Nd, are [[electron capture]] and [[positron decay]], and the primary mode after is [[beta minus decay]]. The primary [[decay product]]s before 142Nd are element Pr ([[praseodymium]]) isotopes and the primary products after are element Pm ([[promethium]]) isotopes.

== History ==
Neodymium was discovered by Baron [[Carl Auer von Welsbach]], an [[Austria]]n [[chemist]], in [[Vienna]] in 1885. He separated neodymium, as well as the element [[praseodymium]], from a material known as [[didymium]] by means of fractional crystallization of the double ammonium nitrate tetrahydrates from nitric acid, while following the separation by [[spectroscopic]] analysis; however, it was not isolated in relatively pure form until 1925. The name neodymium is derived from the [[Greek language|Greek]] words ''neos'', new, and ''didymos'', twin. Neodymium is frequently [[Misspelling|misspelled]] as neody'''n'''ium.<ref name=history>{{cite book|url=http://books.google.com/books?id=j-Xu07p3cKwC| pages= 268–270|title = Nature's building blocks: an A-Z guide to the elements| author =John Emsley| publisher= Oxford University Press| year = 2003| isbn = 0198503407}}</ref>

Double nitrate crystallization was the means of commercial neodymium purification until the 1950s. Lindsay Chemical Division was the first to commercialize large-scale ion-exchange purification of neodymium. Starting in the 1950s, high purity (e.g. 99+%) neodymium was primarily obtained through an [[ion exchange]] process from [[monazite]], a mineral rich in rare earth elements. The metal itself is obtained through [[electrolysis]] of its [[halide]] [[salt]]s. Currently, most neodymium is extracted from [[bastnäsite]], (Ce,La,Nd,Pr)CO3F, and purified by solvent extraction. Ion-exchange purification is reserved for preparing the highest purities (typically >99.99 %). The evolving technology, and improved purity of commercially available neodymium oxide, was reflected in the appearance of neodymium glass made therefrom that resides in collections today. Early neodymium glass made in the 1930s, have a more reddish or orange tinge than modern versions, which are more cleanly purple, due to the difficulties in removing the last traces of praseodymium when the fractional crystallization technology had to be relied on.

== Occurrence and production==
[[File:Bastnaesite - Kischtimsk, Ural.jpg|thumb|Bastnäsite]]
Neodymium is never found in nature as the free element; rather, it occurs in ores such as [[monazite]] and [[bastnäsite]] that contain small amounts of all the rare earth metals. The main mining areas are [[China]], [[United States]], [[Brazil]], [[India]], [[Sri Lanka]] and [[Australia]]; and reserves of neodymium are estimated as about 8 million tonnes. Although it belongs to "rare earth metals," neodymium is not rare at all - its abundance in the [[Earth]] crust is about 38 mg/kg, which is the second among rare-earth elements after [[cerium]]. The world production of neodymium is about 7,000 tonnes per year.<ref name=history/>

== Applications ==
[[Image:Neodymag.jpg|thumb|left|Neodymium magnet on a bracket from a [[hard drive]].]]
*[[Neodymium magnet]]s are the strongest permanent [[magnet]]s known - [[Neodymium magnet|Nd2Fe14B]]. These magnets are cheaper, lighter, and stronger than [[samarium-cobalt magnet]]s. Neodymium magnets appear in products such as [[microphone]]s, professional [[loudspeaker]]s, in-ear [[headphone]]s, [[guitar]] and [[bass guitar]] [[pick-ups]] and computer [[hard disk]]s where low mass, small volume, or strong magnetic fields are required. Neodymium magnet electric motors have also been responsible for the development of purely electrical model aircraft within the first decade of the 21st century, to the point that these are displacing internal combustion powered models internationally. Likewise, due to this high magnetic-flux capacity, it is heavily used in the electric motors of hybrid automobiles.
*Neodymium is a component of [[didymium]] used for coloring glass to make [[welding|welder]]'s and glass-blower's goggles. The sharp absorption bands obliterate the strong sodium emission at 589 nm.
*Neodymium has an unusually large specific heat capacity at liquid-helium temperatures, so is useful in [[cryocoolers]]
*Neodymium lamps are incandescent lamps containing neodymium in the glass to filter out yellow light, resulting in a whiter light more like sunlight
*Neodymium colors [[glass]] in delicate shades ranging from pure violet through wine-red and warm grey. Light transmitted through such glass shows unusually sharp [[absorption band]]s; the glass is used in [[astronomy|astronomical work]] to produce sharp bands by which [[spectral line]]s may be calibrated. Neodymium is also used to remove the green colour caused by [[iron]] contaminants from glass.
*Neodymium salts are used as a colourant for [[vitreous enamel|enamels]].
*Probably because of similarities to Ca2+, Nd3+ has been reported<ref>Y. Wei et al. "The Effect of Neodymium (Nd3+) on Some Physiological Activities in Oilseed Rape during Calcium (Ca2+) Starvation" [http://www.regional.org.au/au/gcirc/2/399.htm 10th International Rapeceed Congress]</ref> to promote plant growth. Rare earth element compounds are frequently used in China as [[fertilizer]].
*[[Samarium-neodymium dating]] is useful for determining the age relationships of rocks<ref>{{cite web| url=http://news.bbc.co.uk/2/hi/science/nature/7639024.stm | title =Team finds Earth's 'oldest rocks' | publisher =BBC news| accessdate = 2009-06-06}}</ref> and meteorites.
*Size and strength of volcanic eruption can be predicted by scanning for neodymium [[isotope]]s. Small and large volcanic eruptions produce lava with different neodymium isotope composition. From the composition of isotopes, scientists predict how big the coming eruption will be, and use this information to warn residents of the intensity of the eruption.
*Certain transparent materials with a small concentration of neodymium [[ion]]s can be used in [[laser]]s as [[gain medium|gain media]] for infrared wavelengths (1054-1064 nm), e.g. [[Nd:YAG laser|Nd:YAG]] (yttrium aluminium garnet), [[Neodymium-doped yttrium lithium fluoride|Nd:YLF]] (yttrium lithium fluoride), [[Neodymium-doped yttrium orthovanadate|Nd:YVO4]] (yttrium orthovanadate), and Nd:glass. The current laser at the UK [[Atomic Weapons Establishment]] (AWE), the HELEN (High Energy Laser Embodying Neodymium) 1-[[Watt#Multiples|terawatt]] neodymium-glass laser, can access the midpoints of pressure and temperature regions and is used to acquire data for modeling on how density, temperature and pressure interact inside warheads. HELEN can create plasmas of around 106 [[Kelvin|K]], from which opacity and transmission of radiation are measured.<ref>{{cite journal|doi=10.1364/AO.41.003497|title=Multipass Reconfiguration of the HELEN Nd:Glass Laser at the Atomic Weapons Establishment|year=2002|author=Norman, Michael J.; Andrew, James E.; Bett, Thomas H.; Clifford, Roger K.; England, John E.; Hopps, Nicholas W.; Parker, Kenneth W.; Porter, Kenneth; Stevenson, Mark|journal=Applied Optics|volume=41|pages=3497}}</ref>

== Neodymium glass ==
[[Image:Laser glass slabs.jpg|thumb|left|300px|Neodymium doped glass slabs used in extremely powerful lasers for [[inertial confinement fusion]].]]
Neodymium [[glass]] (Nd:glass) is produced by the inclusion of [[neodymium(III) oxide|neodymium oxide]] (Nd2O3) in the glass melt. In daylight or [[Incandescent light bulb|incandescent]] light neodymium glass appears lavender, but it appears pale blue under [[Fluorescent lamp|fluorescent]] lighting.

Neodymium glass [[solid-state laser]]s are used in extremely high power ([[1 E11 W#1 terawatt|terawatt]] scale), high energy ([[megajoule]]s) multiple beam systems for [[inertial confinement fusion]] (see last bulleted paragraph above). Nd:glass lasers are usually [[nonlinear optics|frequency tripled]] to the [[optical frequency multiplier|third harmonic]] at 351 nm in laser fusion devices.

Neodymium glass is becoming widely used in [[incandescent light bulb]]s, to provide a more "natural" light. It has been patented for use in automobile rear-view mirrors, to reduce the glare at night.

The first commercial use of purified neodymium was in glass coloration, starting with experiments by Leo Moser in November 1927. The resulting "Alexandrite" glass remains a signature color of the Moser glassworks to this day. Neodymium glass was widely emulated in the early 1930s by American glasshouses, most notably Heisey, Fostoria ("wisteria"), Cambridge ("heatherbloom"), and Steuben ("wisteria"), and elsewhere (e.g. Lalique, in [[France]], or Murano). Tiffin's "twilight" remained in production from about 1950 to about 1980.<ref>{{cite web|url=http://coloradosprings.yourhub.com/CrippleCreekTellerCounty/Stories/Arts/Story~443258.aspx|title =Chameleon Glass Changes Color|accessdate=2009-06-06}}</ref> Current sources include glassmakers in the [[Czech Republic]], the [[United States]], and [[China]].

The sharp absorption bands of neodymium cause the glass color to change under different lighting conditions, being reddish-purple under [[daylight]] or yellow [[incandescent light]], but blue under white [[fluorescent light]]ing, or greenish under trichromatic lighting. This color-change phenomenon is highly prized by collectors. In combination with [[gold]] or [[selenium]], beautiful red colors result. Since neodymium coloration depends upon "[[Forbidden mechanism|forbidden]]" f-f transitions deep within the atom, there is relatively little influence on the color from the chemical environment, so the color is impervious to the thermal history of the glass. However, for the best color, [[iron]]-containing impurities need to be minimized in the [[silica]] used to make the glass. The same "forbiddenness" of the f-f transitions makes [[rare-earth]] colorants less intense than those provided by most d-transition elements, so more has to be used in a glass to achieve the desired color intensity. The original Moser recipe used about 5% of neodymium oxide in the glass melt, a sufficient quantity such that Moser referred to these as being "rare earth doped" glasses. Being a strong base, that level of neodymium would have affected the melting properties of the glass, and the [[Calcium oxide|lime]] content of the glass might have had to be adjusted accordingly.<ref>{{cite book|page=102|url=http://books.google.com/books?id=KbZkxDyeG18C&pg=PA102| title=Dictionary of glass: materials and techniques| author=Charles Bray| publisher= University of Pennsylvania Press| year = 2001| isbn=081223619X}}</ref>

== Precautions ==
Neodymium metal dust is a combustion and explosion hazard.

Neodymium compounds, like all rare earth metals, are of low to moderate toxicity; however its toxicity has not been thoroughly investigated. Neodymium dust and salts are very irritating to the eyes and [[mucous membrane]]s, and moderately irritating to skin. Breathing the dust can cause lung [[embolism]]s, and accumulated exposure damages the liver. Neodymium also acts as an [[anticoagulant]], especially when given intravenously.<ref name=history/>

Neodymium magnets have been tested for medical uses such as magnetic braces and bone repair, but [[biocompatibility]] issues have prevented widespread application. Commercially available magnets made from Neodymium are exceptionally strong, and can attract each other from large distances. If not handled carefully, they could come together very quickly and forcefully, causing injuries. For example, a person lost part of his finger when two magnets he was using snapped together from 50 cm away.<ref>{{cite web | last = Swain
| first = Frank | title = How to remove a finger with two super magnets| publisher = Seed Media Group LLC | date = March 6, 2009 | url = http://scienceblogs.com/sciencepunk/2009/03/how_to_remove_a_finger_with_tw.php| accessdate = 2009-06-28}}</ref> Another danger is when two such magnets snap together, the force of the hit often causes them to shatter, sending sharp pieces flying around, potentially causing serious injuries.<ref name=history/>

==See also==
*[[Neodymium magnet]] (NIB or Nd2Fe14B)

==References==
{{reflist|2}}

==Books==
*"The Industrial Chemistry of the Lanthanons, Yttrium, Thorium and Uranium", by R.J. Callow, Pergamon Press 1967.
*Lindsay Chemical Division, American Potash and Chemical Corporation, Price List, 1960.
*"Chemistry of the Lanthanons", by R.C. Vickery, Butterworths 1953.

== External links ==
{{Commons|Neodymium}}
{{wiktionary|neodymium}}
*[http://minerals.usgs.gov/minerals/pubs/commodity/rare_earths/ USGS Rare Earth Commodity Summary 2006]
*[http://www.webelements.com/webelements/elements/text/Nd/index.html WebElements.com – Neodymium]
*[http://education.jlab.org/itselemental/ele060.html It's Elemental – Neodymium]
{{clear}}
{{Compact periodic table}}

[[Category:Chemical elements]]
[[Category:Lanthanides]]
[[Category:Neodymium]]



[[ar:نيوديميوم]]
[[az:Neodim]]
[[bn:নিওডিমিয়াম]]
[[be:Неадым]]
[[bs:Neodijum]]
[[bg:Неодим]]
[[ca:Neodimi]]
[[cs:Neodym]]
[[co:Neodimiu]]
[[cy:Neodymiwm]]
[[da:Neodym]]
[[de:Neodym]]
[[et:Neodüüm]]
[[el:Νεοδύμιο]]
[[es:Neodimio]]
[[eo:Neodimo]]
[[eu:Neodimio]]
[[fa:نئودیمیم]]
[[fr:Néodyme]]
[[fur:Neodimi]]
[[gv:Niodymium]]
[[gl:Neodimio]]
[[hak:Ńg]]
[[ko:네오디뮴]]
[[hy:Նեոդիում]]
[[hi:नियोडाइमियम]]
[[hr:Neodimij]]
[[io:Neodimio]]
[[id:Neodimium]]
[[it:Neodimio]]
[[he:נאודימיום]]
[[jv:Neodimium]]
[[ht:Neyodim]]
[[la:Neodymium]]
[[lv:Neodīms]]
[[lb:Neodym]]
[[lt:Neodimis]]
[[lij:Neodimio]]
[[jbo:jinmrne,odimi]]
[[hu:Neodímium]]
[[ml:നിയോഡൈമിയം]]
[[mr:नियोडायमियम]]
[[ms:Neodimium]]
[[nl:Neodymium]]
[[ja:ネオジム]]
[[no:Neodym]]
[[nn:Neodym]]
[[pnb:نیوڈائمیم]]
[[pl:Neodym]]
[[pt:Neodímio]]
[[ro:Neodim]]
[[qu:Neodimyu]]
[[ru:Неодим]]
[[sah:Неодимиум]]
[[stq:Neodymium]]
[[scn:Neodimiu]]
[[simple:Neodymium]]
[[sk:Neodým]]
[[sl:Neodim]]
[[sr:Неодијум]]
[[sh:Neodijum]]
[[fi:Neodyymi]]
[[sv:Neodym]]
[[ta:நியோடைமியம்]]
[[th:นีโอดิเมียม]]
[[tr:Neodimyum]]
[[uk:Неодим]]
[[ur:Neodymium]]
[[ug:نېئودىي]]
[[vi:Neodymi]]
[[zh:钕]]

Wikipedia - User contributions [en]

Neodymium