Editing Ytterbium

{{Distinguish|yttrium}}
{{infobox ytterbium}}
'''Ytterbium''' is a [[chemical element]]; it has [[Symbol (chemistry)|symbol]] '''Yb''' and [[atomic number]] 70. It is a metal, the fourteenth and penultimate element in the [[lanthanide]] series, which is the basis of the relative stability of its +2 [[oxidation state]]. Like the other lanthanides, its most common oxidation state is +3, as in its [[oxide]], [[halide]]s, and other compounds. In [[aqueous solution]], like compounds of other late lanthanides, soluble ytterbium compounds form complexes with nine water molecules. Because of its closed-shell electron configuration, its density, melting point and boiling point are much lower than those of most other lanthanides.

In 1878, Swiss chemist [[Jean Charles Galissard de Marignac]] separated from the rare earth "erbia", another independent component, which he called "[[ytterbia]]", for [[Ytterby]], the village in Sweden near where he found the new component of [[erbium]]. He suspected that ytterbia was a compound of a new element that he called "ytterbium". Four elements were named after the village, the others being [[yttrium]], [[terbium]], and [[erbium]]. In 1907, the new earth "lutecia" was separated from ytterbia, from which the element "lutecium", now [[lutetium]], was extracted by [[Georges Urbain]], [[Carl Auer von Welsbach]], and [[Charles James (chemist)|Charles James]]. After some discussion, Marignac's name "ytterbium" was retained. A relatively pure sample of the metal was first obtained in 1953. At present, ytterbium is mainly used as a [[dopant]] of stainless steel or [[active laser medium|active laser media]], and less often as a [[gamma ray]] source.

Natural ytterbium is a mixture of seven stable isotopes, which altogether are present at concentrations of 0.3 [[parts per million]]. This element is mined in China, the United States, Brazil, and India in form of the minerals [[monazite]], [[euxenite]], and [[xenotime]]. The ytterbium concentration is low because it is found only among many other [[rare-earth elements]]. It is among the least abundant. Once extracted and prepared, ytterbium is somewhat hazardous as an eye and skin irritant. The metal is a fire and explosion hazard.

==Characteristics==

===Physical properties===
Ytterbium is a soft, [[malleability|malleable]] and [[ductility|ductile]] [[chemical element]]. When freshly prepared, it is less golden than cesium. It is a [[rare-earth element]], and it is readily dissolved by the strong [[mineral acid]]s. <ref name="CRC">{{cite book| author = Hammond, C. R. |title = The Elements, in Handbook of Chemistry and Physics |edition = 81st| publisher =CRC press| date = 2000| isbn = 978-0-8493-0481-1}}</ref>

Ytterbium has three [[Allotropy|allotropes]] labeled by the Greek letters alpha, beta and gamma. Their transformation temperatures are −13&nbsp;°[[Celsius|C]] and 795&nbsp;°C,<ref name="CRC" /> although the exact transformation temperature depends on the [[pressure]] and [[stress (mechanics)|stress]].<ref name="alpha-Yb" /> The beta allotrope (6.966&nbsp;g/cm<sup>3</sup>) exists at room temperature, and it has a [[face-centered cubic]] [[crystal structure]]. The high-temperature gamma allotrope (6.57&nbsp;g/cm<sup>3</sup>) has a [[body-centered cubic]] crystalline structure.<ref name="CRC" /> The alpha allotrope (6.903&nbsp;g/cm<sup>3</sup>) has a [[hexagonal crystal system|hexagonal]] crystalline structure and is stable at low temperatures.<ref name="Holl" /> 

The beta allotrope has a metallic [[electrical conductivity]] at normal atmospheric pressure, but it becomes a [[semiconductor]] when exposed to a pressure of about 16,000 [[atmospheric pressure|atmospheres]] (1.6&nbsp;[[gigapascal|GPa]]). Its electrical [[resistivity]] increases ten times upon compression to 39,000 atmospheres (3.9&nbsp;GPa), but then drops to about 10% of its room-temperature resistivity at about 40,000&nbsp;atm (4.0&nbsp;GPa).<ref name="CRC" /><ref name="history" />

In contrast to the other rare-earth metals, which usually have [[antiferromagnetic]] and/or [[ferromagnetic]] properties at low [[temperature]]s, ytterbium is [[paramagnetic]] at temperatures above 1.0 [[kelvin]].<ref>Jackson, M. (2000). [http://www.irm.umn.edu/quarterly/irmq10-3.pdf "Magnetism of Rare Earth"]. The IRM quarterly 10(3): 1</ref> However, the alpha allotrope is [[diamagnetic]].<ref name="alpha-Yb">{{Cite journal | last1 = Bucher | first1 = E. | last2 = Schmidt | first2 = P. | last3 = Jayaraman | first3 = A. | last4 = Andres | first4 = K. | last5 = Maita | first5 = J. | last6 = Nassau | first6 = K. | last7 = Dernier | first7 = P. | doi = 10.1103/PhysRevB.2.3911 | title = New First-Order Phase Transition in High-Purity Ytterbium Metal | journal = Physical Review B | volume = 2 | issue = 10 | pages = 3911 | year = 1970 |bibcode = 1970PhRvB...2.3911B }}</ref> With a [[melting point]] of 824&nbsp;°C and a [[boiling point]] of 1196&nbsp;°C, ytterbium has the smallest liquid range of all the metals.<ref name="CRC" />

Contrary to most other lanthanides, which have a close-packed hexagonal lattice, ytterbium crystallizes in the face-centered cubic system. Ytterbium has a density of 6.973&nbsp;g/cm<sup>3</sup>, which is significantly lower than those of the neighboring lanthanides, [[thulium]] (9.32&nbsp;g/cm<sup>3</sup>) and [[lutetium]] (9.841&nbsp;g/cm<sup>3</sup>). Its melting and boiling points are also significantly lower than those of thulium and lutetium. This is due to the closed-shell electron configuration of ytterbium ([Xe] 4f<sup>14</sup> 6s<sup>2</sup>), which causes only the two 6s electrons to be available for [[metallic bonding]] (in contrast to the other lanthanides where three electrons are available) and increases ytterbium's [[metallic radius]].<ref name="Holl" />

===Chemical properties===
Ytterbium metal tarnishes slowly in air, taking on a golden or brown hue. Finely dispersed ytterbium readily oxidizes in air and under oxygen. Mixtures of powdered ytterbium with [[polytetrafluoroethylene]] or [[hexachloroethane]] burn with an emerald-green flame.<ref>{{Cite journal | last1 = Koch | first1 = E. C. | last2 = Weiser | first2 = V. | last3 = Roth | first3 = E. | last4 = Knapp | first4 = S. | last5 = Kelzenberg | first5 = S. | title = Combustion of Ytterbium Metal | doi = 10.1002/prep.201100141 | journal = Propellants, Explosives, Pyrotechnics | volume = 37 | pages = 9–11 | year = 2012 }}</ref> Ytterbium reacts with [[hydrogen]] to form various [[non-stoichiometric compound|non-stoichiometric]] [[hydride]]s. Ytterbium dissolves slowly in water, but quickly in acids, liberating hydrogen.<ref name="Holl" />

Ytterbium is quite [[electropositive]], and it reacts slowly with cold water and quite quickly with hot water to form ytterbium(III) hydroxide:<ref name="webelements" />
:2 Yb (s) + 6 H<sub>2</sub>O (l) → 2 Yb(OH)<sub>3</sub> (aq) + 3 H<sub>2</sub> (g)

Ytterbium reacts with all the [[halogen]]s:<ref name="webelements" />
:2 Yb (s) + 3 F<sub>2</sub> (g) → 2 YbF<sub>3</sub> (s) [white]
:2 Yb (s) + 3 Cl<sub>2</sub> (g) → 2 YbCl<sub>3</sub> (s) [white]
:2 Yb (s) + 3 Br<sub>2</sub> (l) → 2 YbBr<sub>3</sub> (s) [white]
:2 Yb (s) + 3 I<sub>2</sub> (s) → 2 YbI<sub>3</sub> (s) [white]

The ytterbium(III) ion absorbs light in the [[near-infrared]] range of wavelengths, but not in [[visible light]], so [[ytterbia]], Yb<sub>2</sub>O<sub>3</sub>, is white in color and the salts of ytterbium are also colorless. Ytterbium dissolves readily in dilute [[sulfuric acid]] to form solutions that contain the colorless Yb(III) ions, which exist as nonahydrate complexes:<ref name="webelements">{{cite web| url =https://www.webelements.com/ytterbium/chemistry.html| title =Chemical reactions of Ytterbium| publisher=Webelements| access-date=2009-06-06}}</ref>

:2 Yb (s) + 3 H<sub>2</sub>SO<sub>4</sub> (aq) + 18 {{chem|H|2|O}} (l) → 2 [Yb(H<sub>2</sub>O)<sub>9</sub>]<sup>3+</sup> (aq) + 3 {{chem|SO|4|2-}} (aq) + 3 H<sub>2</sub> (g)

===Yb(II) vs. Yb(III)===
Although usually trivalent, ytterbium readily forms divalent compounds. This behavior is unusual for [[lanthanide]]s, which almost exclusively form compounds with an oxidation state of +3. The +2 state has a valence [[electron configuration]] of 4''f''<sup>14</sup> because the fully filled ''f''-shell gives more stability. The yellow-green ytterbium(II) ion is a very strong [[reducing agent]] and decomposes water, releasing [[hydrogen]], and thus only the colorless ytterbium(III) ion occurs in [[aqueous solution]]. [[Samarium]] and [[thulium]] also behave this way in the +2 state, but [[europium]](II) is stable in aqueous solution. Ytterbium metal behaves similarly to europium metal and the alkaline earth metals, dissolving in ammonia to form blue [[electride]] salts.<ref name="Holl" />

===Isotopes===
{{Main|Isotopes of ytterbium}}
Natural ytterbium is composed of seven stable [[isotope]]s: <sup>168</sup>Yb, <sup>170</sup>Yb, <sup>171</sup>Yb, <sup>172</sup>Yb, <sup>173</sup>Yb, <sup>174</sup>Yb, and <sup>176</sup>Yb, with <sup>174</sup>Yb being the most common, at 31.8% of the [[natural abundance]]). Thirty-two [[radioisotope]]s have been observed, with the most stable ones being <sup>169</sup>Yb with a [[half-life]] of 32.0 days, <sup>175</sup>Yb with a half-life of 4.18 days, and <sup>166</sup>Yb with a half-life of 56.7 hours. All of the remaining [[radioactive]] isotopes have half-lives that are less than two hours, and most of these have half-lives under 20 minutes. Ytterbium also has 12 [[meta state]]s, with the most stable being <sup>169m</sup>Yb (''t''<sub>1/2</sub> 46 seconds).<ref name="nucleonica">{{cite web |url=http://www.nucleonica.net/unc.aspx |title=Nucleonica: Universal Nuclide Chart |date=2007–2011 |publisher=Nucleonica |access-date=July 22, 2011}}</ref>{{NUBASE2020|ref}}

The isotopes of ytterbium range from <sup>149</sup>Yb to <sup>187</sup>Yb.{{NUBASE2020|ref}}<ref name=PRL132.7>{{cite journal |first1=O. B. |last1=Tarasov |first2=A. |last2=Gade |first3=K. |last3=Fukushima |display-authors=et al. |title=Observation of New Isotopes in the Fragmentation of <sup>198</sup>Pt at FRIB |journal=Physical Review Letters |volume=132 |number=72501 |date=2024 |page=072501 |doi=10.1103/PhysRevLett.132.072501|pmid=38427880 |bibcode=2024PhRvL.132g2501T }}</ref> The primary [[decay mode]] of ytterbium isotopes lighter than the most abundant stable isotope, <sup>174</sup>Yb, is [[electron capture]], and the primary decay mode for those heavier than <sup>174</sup>Yb is [[beta decay]]. The primary [[decay product]]s of ytterbium isotopes lighter than <sup>174</sup>Yb are [[thulium]] isotopes, and the primary decay products of ytterbium isotopes with heavier than <sup>174</sup>Yb are [[lutetium]] isotopes.<ref name="nucleonica" />{{NUBASE2020|ref}}

==Occurrence==
[[File:Euxenite - Vegusdal, Norvegia 01.jpg|thumb|[[Euxenite]] ]]
Ytterbium is found with other [[rare-earth element]]s in several rare [[mineral]]s. It is most often recovered commercially from [[monazite]] sand (0.03% ytterbium). The element is also found in [[euxenite]] and [[xenotime]]. The main mining areas are China, the United States, [[Brazil]], India, [[Sri Lanka]], and Australia. Reserves of ytterbium are estimated as one million [[tonne]]s. Ytterbium is normally difficult to separate from other rare earths, but [[ion-exchange]] and [[solvent extraction]] techniques developed in the mid- to late 20th century have simplified separation. [[chemical compound|Compounds]] of ytterbium are rare and have not yet been well characterized. The abundance of ytterbium in the Earth's crust is about 3&nbsp;mg/kg.<ref name="history">{{cite book|url=https://archive.org/details/naturesbuildingb0000emsl|url-access=registration| pages= [https://archive.org/details/naturesbuildingb0000emsl/page/492 492]–494|title = Nature's building blocks: an A-Z guide to the elements| author =Emsley, John | publisher= Oxford University Press| date = 2003| isbn = 978-0-19-850340-8}}</ref> 

As an even-numbered lanthanide, in accordance with the [[Oddo–Harkins rule]], ytterbium is significantly more abundant than its immediate neighbors, [[thulium]] and [[lutetium]], which occur in the same concentrate at levels of about 0.5% each. The world production of ytterbium is only about 50 tonnes per year, reflecting that it has few commercial applications.<ref name="history" /> Microscopic traces of ytterbium are used as a [[dopant]] in the [[Yttrium aluminium garnet|Yb:YAG laser]], a [[solid-state laser]] in which ytterbium is the element that undergoes [[stimulated emission]] of [[electromagnetic radiation]].<ref>{{Cite journal | last1 = Lacovara | first1 = P. | last2 = Choi | first2 = H. K. | last3 = Wang | first3 = C. A. | last4 = Aggarwal | first4 = R. L. | last5 = Fan | first5 = T. Y. | title = Room-Temperature Diode-Pumped Yb:YAG laser | doi = 10.1364/OL.16.001089 | journal = Optics Letters | volume = 16 | issue = 14 | pages = 1089–1091 | year = 1991 | pmid = 19776885| bibcode = 1991OptL...16.1089L }}</ref>

Ytterbium is often the most common substitute in [[yttrium]] minerals. In very few known cases/occurrences ytterbium prevails over yttrium, as, e.g., in [[xenotime]]-(Yb). A report of native ytterbium from the Moon's [[regolith]] is known.<ref>{{cite web |url=https://www.mindat.org/min-41858.html |title=Mindat.org |author=Hudson Institute of Mineralogy |date=1993–2018 |website=www.mindat.org |access-date=7 April 2018}}</ref>

==Production==
It is relatively difficult to separate ytterbium from other lanthanides due to its similar properties. As a result, the process is somewhat long. First, minerals such as [[monazite]] or [[xenotime]] are dissolved into various acids, such as [[sulfuric acid]]. Ytterbium can then be separated from other lanthanides by [[ion exchange]], as can other lanthanides. The solution is then applied to a [[resin]], to which different lanthanides bind with different affinities. This is then dissolved using [[complexing agent]]s, and due to the different types of bonding exhibited by the different lanthanides, it is possible to isolate the compounds.<ref>{{Cite journal | last1 = Gelis | first1 = V. M. | last2 = Chuveleva | first2 = E. A. | last3 = Firsova | first3 = L. A. | last4 = Kozlitin | first4 = E. A. | last5 = Barabanov | first5 = I. R. | title = Optimization of Separation of Ytterbium and Lutetium by Displacement Complexing Chromatography | doi = 10.1007/s11167-005-0530-6 | journal = Russian Journal of Applied Chemistry | volume = 78 | issue = 9 | pages = 1420 | year = 2005 | s2cid = 94642269 }}</ref><ref>{{Cite journal | last1 = Hubicka | first1 = H. | last2 = Drobek | first2 = D. | doi = 10.1016/S0304-386X(97)00040-6 | title = Anion-Exchange Method for Separation of Ytterbium from Holmium and Erbium | journal = Hydrometallurgy | volume = 47 | pages = 127–136 | year = 1997 | issue = 1 | bibcode = 1997HydMe..47..127H }}</ref>

Ytterbium is separated from other rare earths either by [[ion exchange]] or by reduction with sodium amalgam. In the latter method, a buffered acidic solution of trivalent rare earths is treated with molten sodium-mercury alloy, which reduces and dissolves Yb<sup>3+</sup>. The alloy is treated with [[hydrochloric acid]]. The metal is extracted from the solution as oxalate and converted to oxide by heating. The oxide is reduced to metal by heating with [[lanthanum]], [[aluminium]], [[cerium]] or [[zirconium]] in high vacuum. The metal is purified by sublimation and collected over a condensed plate.<ref name="patnaik">{{cite book|last =Patnaik|first =Pradyot |date = 2003|title =Handbook of Inorganic Chemical Compounds|publisher = McGraw-Hill|pages = 973–975|isbn =978-0-07-049439-8| url= https://books.google.com/books?id=Xqj-TTzkvTEC&pg=PA243|access-date = 2009-06-06}}</ref>

==Compounds==
[[File:Ytterbium(III) oxide.jpg|thumb|[[Ytterbium(III) oxide]]]]
{{See also|Category:Ytterbium compounds}}
The chemical behavior of ytterbium is similar to that of the rest of the [[lanthanide]]s. Most ytterbium compounds are found in the +3 oxidation state, and its salts in this oxidation state are nearly colorless. Like [[europium]], [[samarium]], and [[thulium]], the trihalides of ytterbium can be reduced to the dihalides by [[hydrogen]], [[zinc]] dust, or by the addition of metallic ytterbium.<ref name="Holl" /> The +2 oxidation state occurs only in solid compounds and reacts in some ways similarly to the [[alkaline earth metal]] compounds; for example, ytterbium(II) oxide (YbO) shows the same structure as [[calcium oxide]] (CaO).<ref name="Holl">{{cite book|publisher=Walter de Gruyter|date=1985|edition=91–100|pages=1265–1279|isbn=978-3-11-007511-3|title=Lehrbuch der Anorganischen Chemie|first=Arnold F.|last=Holleman|author2=Wiberg, Egon|author3=Wiberg, Nils|language=de|chapter=Die Lanthanoide}}</ref>

===Halides===
[[File:Kristallstruktur Lanthanoid-C-Typ.png|thumb|right|Crystal structure of [[ytterbium(III) oxide]]]]
Ytterbium forms both dihalides and trihalides with the [[halogen]]s [[fluorine]], [[chlorine]], [[bromine]], and [[iodine]]. The dihalides are susceptible to oxidation to the trihalides at room temperature and disproportionate to the trihalides and metallic ytterbium at high temperature:<ref name="Holl" />

:3 YbX<sub>2</sub> → 2 YbX<sub>3</sub> + Yb (X = [[fluorine|F]], [[chlorine|Cl]], [[bromine|Br]], [[iodine|I]])

Some ytterbium halides are used as [[reagent]]s in [[organic synthesis]]. For example, [[ytterbium(III) chloride]] (YbCl<sub>3</sub>) is a [[Lewis acid]] and can be used as a [[catalyst]] in the [[Aldol reaction|Aldol]]<ref>{{Cite journal | last1 = Lou | first1 = S. | last2 = Westbrook | first2 = J. A. | last3 = Schaus | first3 = S. E. | doi = 10.1021/ja045981k | title = Decarboxylative Aldol Reactions of Allyl β-Keto Esters via Heterobimetallic Catalysis | journal = Journal of the American Chemical Society | volume = 126 | issue = 37 | pages = 11440–11441 | year = 2004 | pmid = 15366881| bibcode = 2004JAChS.12611440L }}</ref> and [[Diels–Alder reaction]]s.<ref>{{Cite journal | last1 = Fang | first1 = X. | last2 = Watkin | first2 = J. G. | last3 = Warner | first3 = B. P. | doi = 10.1016/S0040-4039(99)02090-0 | title = Ytterbium Trichloride-Catalyzed Allylation of Aldehydes with Allyltrimethylsilane | journal = Tetrahedron Letters | volume = 41 | issue = 4 | pages = 447 | year = 2000 | url = https://zenodo.org/record/1259721 }}</ref> [[Ytterbium(II) iodide]] (YbI<sub>2</sub>) may be used, like [[samarium(II) iodide]], as a [[reducing agent]] for [[coupling reactions]].<ref>{{Cite journal | last1 = Girard | first1 = P. | last2 = Namy | first2 = J. L. | last3 = Kagan | first3 = H. B. | doi = 10.1021/ja00528a029 | title = Divalent Lanthanide Derivatives in Organic Synthesis. 1. Mild Preparation of Samarium Iodide and Ytterbium Iodide and Their Use as Reducing or Coupling Agents | journal = Journal of the American Chemical Society | volume = 102 | issue = 8 | pages = 2693 | year = 1980 | bibcode = 1980JAChS.102.2693G }}</ref> [[Ytterbium(III) fluoride]] (YbF<sub>3</sub>) is used as an inert and non-toxic [[tooth filling]] as it continuously releases [[fluoride]] ions, which are good for dental health, and is also a good [[X-ray contrast agent]].<ref name="Enghag">Enghag, Per (2004). ''Encyclopedia of the elements: technical data, history, processing, applications.'' John Wiley & Sons, {{ISBN|978-3-527-30666-4}}, [https://books.google.com/books?id=aff7sEea39EC&pg=PA448 p. 448].</ref>

===Oxides===
Ytterbium reacts with oxygen to form [[ytterbium(III) oxide]] (Yb<sub>2</sub>O<sub>3</sub>), which crystallizes in the "rare-earth C-type sesquioxide" structure which is related to the [[fluorite]] structure with one quarter of the anions removed, leading to ytterbium atoms in two different six coordinate (non-octahedral) environments.<ref>Wells A.F. (1984) ''Structural Inorganic Chemistry'' 5th edition, Oxford Science Publications, {{ISBN|0-19-855370-6}}</ref> Ytterbium(III) oxide can be reduced to [[ytterbium(II) oxide]] (YbO) with elemental ytterbium, which crystallizes in the same structure as [[sodium chloride]].<ref name="Holl" />

===Borides===
Ytterbium dodecaboride (YbB<sub>12</sub>) is a crystalline material that has been studied to understand various electronic and structural properties of many chemically related substances. It is a [[Kondo insulator]].<ref>{{cite journal |title= On the nature of the energy gap in ytterbium dodecaboride YbB<sub>12</sub> |first1= T. S. |last1= Al'tshuler |first2= M. S. |last2= Bresler |journal= Physics of the Solid State |volume= 44 |pages= 1532–1535 |year= 2002 |issue= 8 |doi= 10.1134/1.1501353 |bibcode= 2002PhSS...44.1532A |s2cid= 120575196 }}</ref> It is a [[quantum material]]; under normal conditions, the interior of the bulk crystal is an [[Insulator (electricity)|insulator]] whereas the surface is highly [[conductive]].<ref>{{cite journal |title= Quantum oscillations of electrical resistivity in an insulator |first1= Z. |last1= Xiang |first2= Y. |last2= Kasahara |first3= T. |last3= Asaba |first4= B. |last4= Lawson |first5= C. |last5= Tinsman |first6= Lu |last6= Chen |first7= K. |last7= Sugimoto |first8= S. |last8= Kawaguchi |first9= Y. |last9= Sato |first10= G. |last10= Li |first11= S. |last11= Yao |first12= Y. L. |last12= Chen |first13= F. |last13= Iga |first14= John |last14= Singleton |first15= Y. |last15= Matsuda |first16= Lu |last16= Li |journal= Science |year= 2018 |volume=362 |issue= 6410 |pages= 65–69 |doi=10.1126/science.aap9607 |pmid= 30166438 |arxiv= 1905.05140 |bibcode= 2018Sci...362...65X |s2cid= 206664739 }}</ref> Among the [[rare earth element]]s, ytterbium is one of the few that can form a stable dodecaboride, a property attributed to its comparatively small atomic radius.<ref>{{cite journal |title= Ytterbium and terbium dodecaborides |first1=1 S. J. |last1= La Placa |first2= D. |last2= Noonan |journal= Acta Crystallographica |year= 1963 |volume= 16 |issue=11 |pages= 1182 |doi= 10.1107/S0365110X63003108 |bibcode=1963AcCry..16.1182L |url=https://digital.library.unt.edu/ark:/67531/metadc1255841/ }}</ref>

==History==
[[File:Galissard de Marignac.jpg|thumb|[[Jean Charles Galissard de Marignac]]]]
In 1878, Ytterbium [[discovery of the chemical elements|was discovered by]] the Swiss chemist [[Jean Charles Galissard de Marignac]]. While examining samples of [[gadolinite]], Marignac found a new component in the earth then known as [[erbia]], and he named it ytterbia, for [[Ytterby]], the Swedish village near where he found the new component of erbium. Marignac suspected that ytterbia was a compound of a new element that he called "ytterbium".<ref name="history" /><ref name="Enghag" /><ref name="Weeks">{{cite book |last1=Weeks |first1=Mary Elvira |title=The discovery of the elements |date=1956 |publisher=Journal of Chemical Education |location=Easton, PA |url=https://archive.org/details/discoveryoftheel002045mbp |edition=6th }}</ref><ref name="XVI">{{cite journal |last1=Weeks |first1=Mary Elvira |title=The discovery of the elements. XVI. The rare earth elements |journal=Journal of Chemical Education |date=October 1932 |volume=9 |issue=10 |pages=1751 |doi=10.1021/ed009p1751 |bibcode=1932JChEd...9.1751W }}</ref><ref name="RSYtterbium">{{cite web |title=Ytterbium |url=https://www.rsc.org/periodic-table/element/70/ytterbium |website=Royal Society of Chemistry|date= 2020 |access-date=4 January 2020}}</ref>

In 1907, the French chemist [[Georges Urbain]] separated Marignac's ytterbia into two components: ''neoytterbia'' and ''lutecia''. Neoytterbia later became known as the element ytterbium, and lutecia became known as the element [[lutetium]]. The Austrian chemist [[Carl Auer von Welsbach]] independently isolated these elements from ytterbia at about the same time, but he called them ''aldebaranium'' (''Ad''; after [[Aldebaran]]) and ''cassiopeium''.<ref name="history" /> The American chemist [[Charles James (chemist)|Charles James]] also independently isolated these elements at about the same time.<ref>{{cite web | title = {{sic|Separaton|nolink=y}} of Rare Earth Elements by Charles James | work = National Historic Chemical Landmarks | publisher = American Chemical Society | url = http://www.acs.org/content/acs/en/education/whatischemistry/landmarks/earthelements.html | access-date = 2014-02-21 }}</ref> 

Urbain and Welsbach accused each other of publishing results based on the other party.<ref name="1st">{{cite journal|title=Un nouvel élément, le lutécium, résultant du dédoublement de l'ytterbium de Marignac|journal=Comptes rendus hebdomadaires des séances de l'Académie des Sciences|volume=145|date=1908|url=http://gallica.bnf.fr/ark:/12148/bpt6k3099v/f759.table|pages=759–762|author=Urbain, M.G.|language=fr}}</ref><ref name="Fra">{{cite journal|title=Lutetium und Neoytterbium oder Cassiopeium und Aldebaranium – Erwiderung auf den Artikel des Herrn Auer v. Welsbach|date=1909|journal=Monatshefte für Chemie|volume=31|issue=10|doi=10.1007/BF01530262|first=G. |last=Urbain|page=1|s2cid=101825980|url=https://zenodo.org/record/1859372}}</ref><ref name="Deu">{{cite journal|title=Die Zerlegung des Ytterbiums in seine Elemente|journal=Monatshefte für Chemie|volume=29|issue=2|date=1908|doi=10.1007/BF01558944|pages=181–225|first=Carl A.|last=von Welsbach|s2cid=197766399|url=https://zenodo.org/record/2348610}}</ref> In 1909, the Commission on Atomic Mass, consisting of [[Frank Wigglesworth Clarke]], [[Wilhelm Ostwald]], and Georges Urbain, which was then responsible for the attribution of new element names, settled the dispute by granting priority to Urbain and adopting his names as official ones, based on the fact that the separation of lutetium from Marignac's ytterbium was first described by Urbain.<ref name="1st" /> After Urbain's names were recognized, ''neoytterbium'' was reverted to ''ytterbium''.

The chemical and physical properties of ytterbium could not be determined with any precision until 1953, when the first nearly pure ytterbium metal was produced by using [[ion-exchange]] processes.<ref name="history" /> The price of ytterbium was relatively stable between 1953 and 1998 at about US$1,000/kg.<ref>{{cite news| publisher = USGS| title =Rare-Earth Metals| author = Hedrick, James B. | access-date = 2009-06-06| url =http://minerals.usgs.gov/minerals/pubs/commodity/rare_earths/740798.pdf}}</ref>

==Applications==

===Source of gamma rays===
The <sup>169</sup>Yb [[isotope]] (with a [[half-life]] of 32 days), which is created along with the short-lived <sup>175</sup>Yb isotope (half-life 4.2 days) by [[neutron activation]] during the [[irradiation]] of ytterbium in [[nuclear reactor]]s, has been used as a [[radiation]] source in portable [[X-ray]] machines. Like X-rays, the [[gamma rays]] emitted by the source pass through soft tissues of the body, but are blocked by bones and other dense materials. Thus, small <sup>169</sup>Yb samples (which emit gamma rays) act like tiny X-ray machines useful for [[radiography]] of small objects. Experiments show that radiographs taken with a <sup>169</sup>Yb source are roughly equivalent to those taken with X-rays having energies between 250 and 350&nbsp;keV. <sup>169</sup>Yb is also used in [[nuclear medicine]].<ref>{{cite book|pages=168–169|url=https://books.google.com/books?id=wJqBSA1exqoC| title =Industrial radiology: theory and practice| author= Halmshaw, R. | publisher = Springer| date = 1995| isbn =978-0-412-62780-4}}</ref>

===High-stability atomic clocks===
A pair of experimental atomic clocks based on ytterbium atoms at the [[National Institute of Standards and Technology|National Institute of Standards and Technology (NIST)]] has set a record for stability. NIST physicists reported the ytterbium clocks' ticks are stable to within less than two parts in 1 [[quintillion]] (1 followed by 18 zeros), roughly 10 times better than the previous best published results for other atomic clocks. The clocks would be accurate within a second for a period comparable to the age of the universe. These clocks rely on about 10,000 ytterbium atoms [[Laser cooling|laser-cooled]] to 10 microkelvin (10 millionths of a degree above [[absolute zero]]) and trapped in an [[optical lattice]]—a series of pancake-shaped wells made of laser light. Another laser that "ticks" 518 trillion times per second (518 THz) provokes a transition between two energy levels in the atoms. The large number of atoms is key to the clocks' high stability.<ref>NIST (2013-08-22) [https://www.nist.gov/pml/div688/clock-082213.cfm Ytterbium Atomic Clocks Set Record for Stability].</ref>

Visible light waves oscillate faster than microwaves, hence optical clocks can be more precise than [[caesium]] [[atomic clocks]]. The [[Physikalisch-Technische Bundesanstalt]] is working on several such optical clocks. The model with one single ytterbium ion caught in an [[ion trap]] is highly accurate. The optical clock based on it is exact to 17 digits after the decimal point.<ref>Peik, Ekkehard (2012-03-01). [https://www.ptb.de/cms/en/presseaktuelles/journals-magazines/ptb-news/ptb-news-ausgaben/archivederptb-news/ptb-news-2012/new-pendulum-for-the-ytterbium-clock.html New "pendulum" for the ytterbium clock]. ptb.de.</ref>

===Doping of stainless steel===
Ytterbium can also be used as a [[dopant]] to help improve the grain refinement, strength, and other mechanical properties of [[stainless steel]]. Some ytterbium [[alloy]]s have rarely been used in [[dentistry]].<ref name="CRC" /><ref name="history" />

===Ytterbium as dopant of active media===
The Yb<sup>3+</sup> [[ion]] is used as a [[doping (semiconductors)|doping material]] in [[active laser medium|active laser media]], specifically in [[solid state laser]]s and [[double clad fiber]] lasers. Ytterbium lasers are highly efficient, have long lifetimes and can generate short pulses; ytterbium can also easily be incorporated into the material used to make the laser.<ref>{{cite thesis |last=Ostby |first=Eric |date=2009 |title=Photonic Whispering-Gallery Resonations in New Environments |url=https://thesis.library.caltech.edu/2284/4/03_Ch3_Ostby.pdf
|access-date=21 December 2012 |publisher=[[California Institute of Technology]]}}</ref> Ytterbium lasers commonly radiate in the 1.03–1.12&nbsp;[[μm]] band being [[optical pumping|optically pumped]] at wavelength 900&nbsp;nm–1&nbsp;μm, dependently on the host and application. The small [[quantum defect]] makes ytterbium a prospective dopant for efficient lasers and [[power scaling]].<ref>{{cite journal|doi=10.1070/QE2004v034n03ABEH002621|title=Broadband Radiation Source Based on an Ytterbium-Doped Fibre With Fibre-Length-Distributed Pumping|date=2004|author=Grukh, Dmitrii A.|journal=Quantum Electronics|volume=34|page=247|last2=Bogatyrev|first2=V. A.|last3=Sysolyatin|first3=A. A.|last4=Paramonov|first4=Vladimir M.|last5=Kurkov|first5=Andrei S.|last6=Dianov|first6=Evgenii M.|bibcode = 2004QuEle..34..247G|issue=3 |s2cid=250788004 }}</ref>

The kinetic of excitations in ytterbium-doped materials is simple and can be described within the concept of [[McCumber relation|effective cross-section]]s; for most ytterbium-doped laser materials (as for many other optically pumped gain media), the [[McCumber relation]] holds,<ref name="kouz05">{{cite journal|author=Kouznetsov, D.|author2=Bisson, J.-F.|author3=Takaichi, K.|author4=Ueda, K. |title=Single-mode solid-state laser with short wide unstable cavity|journal=[[Journal of the Optical Society of America B]]|volume=22| issue=8| pages=1605–1619|date=2005|doi=10.1364/JOSAB.22.001605|bibcode=2005JOSAB..22.1605K}}</ref><ref name="mc">
{{cite journal|author=McCumber, D.E. |title= Einstein Relations Connecting Broadband Emission and Absorption Spectra|journal= Physical Review B|volume= 136|issue=4A|pages=954–957|date=1964|doi=10.1103/PhysRev.136.A954|bibcode = 1964PhRv..136..954M }}</ref><ref name="B">{{cite book| author = Becker, P.C.| author2 = Olson, N.A.| author3 = Simpson, J.R. |title =Erbium-Doped Fiber Amplifiers: Fundamentals and Theory| publisher = Academic press| date = 1999}}</ref> although the application to the ytterbium-doped [[composite materials]] was under discussion.<ref name="McCumberA">{{cite journal |author=Kouznetsov, D. |title=Comment on Efficient diode-pumped Yb:Gd<sub>2</sub>SiO<sub>5</sub> laser|journal=Applied Physics Letters |volume=90|date=2007|doi=10.1063/1.2435309 |page=066101|bibcode = 2007ApPhL..90f6101K |issue=6 }}</ref><ref name="McCumberB">{{cite journal |author=Zhao, Guangjun |author2=Su, Liangbi |author3=Xu, Jun |author4=Zeng, Heping |title=Response to Comment on Efficient diode-pumped Yb:Gd<sub>2</sub>SiO<sub>5</sub> laser|journal=Applied Physics Letters |volume=90 |page=066103 |date=2007 |doi=10.1063/1.2435314|bibcode = 2007ApPhL..90f6103Z |issue=6 |doi-access=free }}</ref>

Usually, low concentrations of ytterbium are used. At high concentrations, the ytterbium-doped materials show [[photodarkening]]<ref name="photodarkening">{{cite journal |author=Koponen, Joona J. |author2=Söderlund, Mikko J. |author3=Hoffman, Hanna J. |author4=Tammela, Simo K. T. |name-list-style=amp |title= Measuring photodarkening from single-mode ytterbium doped silica fibers|journal=Optics Express|volume=14 |issue=24 |pages=11539–11544 |doi= 10.1364/OE.14.011539 |date= 2006 |pmid=19529573|bibcode = 2006OExpr..1411539K |s2cid=27830683 |doi-access=free }}</ref>
(glass fibers) or even a switch to broadband emission<ref name="avalanche">{{cite journal
|author=Bisson, J.-F.|author2=Kouznetsov, D.|author3=Ueda, K.|author4=Fredrich-Thornton, S. T.|author5=Petermann, K.|author6=Huber, G.|title=Switching of Emissivity and Photoconductivity in Highly Doped Yb<sup>3+</sup>:Y<sub>2</sub>O<sub>3</sub> and Lu<sub>2</sub>O<sub>3</sub> Ceramics |journal=Applied Physics Letters |volume=90 |page= 201901 |date=2007 |doi=10.1063/1.2739318|bibcode = 2007ApPhL..90t1901B|issue=20 }}</ref> (crystals and ceramics) instead of efficient laser action. This effect may be related with not only overheating, but also with conditions of [[charge compensation]] at high concentrations of ytterbium ions.<ref>{{cite journal|author=Sochinskii, N.V.|author2=Abellan, M.|author3=Rodriguez-Fernandez, J.|author4=Saucedo, E.|author5=Ruiz, C.M.|author6=Bermudez, V. |title=Effect of Yb concentration on the resistivity and lifetime of CdTe:Ge:Yb codoped crystals |date=2007 |journal=Applied Physics Letters |volume=91 |issue=20 |page=202112 |doi=10.1063/1.2815644|bibcode = 2007ApPhL..91t2112S |url=https://digital.csic.es/bitstream/10261/46803/1/ApplPhysLett_91_202112.pdf|hdl=10261/46803|hdl-access=free}}</ref>

Much progress has been made in the power scaling lasers and amplifiers produced with ytterbium (Yb) doped optical fibers. Power levels have increased from the 1&nbsp;kW regimes due to the advancements in components as well as the Yb-doped fibers. Fabrication of Low NA, Large Mode Area fibers enable achievement of near perfect beam qualities (M2<1.1) at power levels of 1.5&nbsp;kW to greater than 2&nbsp;kW at ~1064&nbsp;nm in a broadband configuration.<ref>{{cite journal|doi=10.1038/nphoton.2011.170|title=Doped fibres: Rare-earth fibres power up|journal=Nature Photonics|volume=5|issue=8|pages=466|year=2011|last1=Samson|first1=Bryce|last2=Carter|first2=Adrian|last3=Tankala|first3=Kanishka|bibcode=2011NaPho...5..466S}}</ref> Ytterbium-doped LMA fibers also have the advantages of a larger mode field diameter, which negates the impacts of nonlinear effects such as stimulated [[Brillouin scattering]] and stimulated [[Raman scattering]], which limit the achievement of higher power levels, and provide a distinct advantage over single mode ytterbium-doped fibers.

To achieve even higher power levels in ytterbium-based fiber systems, all factors of the fiber must be considered. These can be achieved only through optimization of all ytterbium fiber parameters, ranging from the core background losses to the geometrical properties, to reduce the splice losses within the cavity. Power scaling also requires optimization of matching passive fibers within the optical cavity.<ref>{{cite web |title=Fiber for Fiber Lasers: Matching Active and Passive Fibers Improves Fiber Laser Performance|url=http://www.laserfocusworld.com/articles/print/volume-48/issue-01/features/matching-active-and-passive-fibers-improves-fiber-laser-performance.html/|date=2012-01-01|publisher=[[Laser Focus World]]}}</ref> The optimization of the ytterbium-doped glass itself through host glass modification of various dopants also plays a large part in reducing the background loss of the glass, improvements in slope efficiency of the fiber, and improved photodarkening performance, all of which contribute to increased power levels in 1&nbsp;μm systems.

===Ion qubits for quantum computing===
The charged ion <sup>171</sup>Yb<sup>+</sup> is used by multiple academic groups and companies as the trapped-ion qubit for [[quantum computing]].<ref name="Olms1">{{cite journal |last1=Olmschenk |first1=S. |title=Manipulation and detection of a trapped Yb171<sup>+</sup> hyperfine qubit |journal=Physical Review A |date=Nov 2007 |volume=76 |issue=5 |pages=052314 |doi=10.1103/PhysRevA.76.052314 |bibcode=2007PhRvA..76e2314O |arxiv=0708.0657 |s2cid=49330988 }}</ref><ref>{{Cite web |title=Quantinuum {{!}} Hardware |url=https://www.quantinuum.com/hardware |access-date=2023-05-21 |website=www.quantinuum.com |language=en}}</ref><ref>{{Cite web |title=IonQ {{!}} Our Trapped Ion Technology |url=https://ionq.com/technology |access-date=2023-05-21 |website=IonQ |language=en}}</ref> [[Quantum entanglement|Entangling]] [[Quantum logic gate|gates]], such as the [[Mølmer–Sørensen gate]], have been achieved by addressing the ions with [[Mode-locking|mode-locked]] pulse lasers.<ref name="hay1">{{cite journal |last1=Hayes |first1=D. |title=Entanglement of Atomic Qubits Using an Optical Frequency Comb |journal=Physical Review Letters |date=Apr 2010 |volume=104 |issue=14 |pages=140501  |doi=10.1103/PhysRevLett.104.140501 |pmid=20481925 |bibcode=2010PhRvL.104n0501H |arxiv=1001.2127 |s2cid=14424109 }}</ref>

===Others===
Ytterbium metal increases its electrical resistivity when subjected to high stresses. This property is used in stress gauges to monitor ground deformations from earthquakes and explosions.<ref name="appl">{{cite book| page = 32| url = https://books.google.com/books?id=F0Bte_XhzoAC&pg=PA32| title = Extractive metallurgy of rare earths| author = Gupta, C.K.| author2 = Krishnamurthy, Nagaiyar| name-list-style = amp | publisher =CRC Press| date = 2004| isbn =978-0-415-33340-5}}</ref>

Currently, ytterbium is being investigated as a possible replacement for [[magnesium]] in high density pyrotechnic payloads for kinematic [[flare (countermeasure)|infrared decoy flares]]. As [[ytterbium(III) oxide]] has a significantly higher [[emissivity]] in the infrared range than [[magnesium oxide]], a higher radiant intensity is obtained with ytterbium-based payloads in comparison to those commonly based on [[magnesium/Teflon/Viton]] (MTV).<ref>{{Cite journal | last1 = Koch | first1 = E. C. | last2 = Hahma | first2 = A. | doi = 10.1002/zaac.201200036 | title = Metal-Fluorocarbon Pyrolants. XIV: High Density-High Performance Decoy Flare Compositions Based on Ytterbium/Polytetrafluoroethylene/Viton® | journal = Zeitschrift für Anorganische und Allgemeine Chemie | volume = 638 | issue = 5 | pages = 721 | year = 2012| doi-access = free }}</ref>

==Precautions==
Although ytterbium is fairly stable chemically, it is stored in airtight containers and in an inert atmosphere such as a nitrogen-filled dry box to protect it from air and moisture.<ref>{{Cite journal | last1 = Ganesan | first1 = M. | last2 = Bérubé | first2 = C. D. | last3 = Gambarotta | first3 = S. | last4 = Yap | first4 = G. P. A. | title = Effect of the Alkali-Metal Cation on the Bonding Mode of 2,5-Dimethylpyrrole in Divalent Samarium and Ytterbium Complexes | doi = 10.1021/om0109915 | journal = Organometallics | volume = 21 | issue = 8 | pages = 1707 | year = 2002 | url = https://figshare.com/articles/Effect_of_the_Alkali-Metal_Cation_on_the_Bonding_Mode_of_2_5-Dimethylpyrrole_in_Divalent_Samarium_and_Ytterbium_Complexes/3768606 }}</ref> All compounds of ytterbium are treated as highly [[toxic]], although studies appear to indicate that the danger is minimal. However, ytterbium compounds cause irritation to human skin and eyes, and some might be [[teratogenic]].<ref>{{cite journal| doi =10.1002/tera.1420110308| date =1975| author =Gale, T.F.| title =The Embryotoxicity of Ytterbium Chloride in Golden Hamsters| volume =11| issue =3| pages =289–95|pmid =807987| journal =Teratology}}</ref> Metallic ytterbium dust can spontaneously combust.<ref>{{Cite journal | last1 = Ivanov | first1 = V. G. | last2 = Ivanov | first2 = G. V. | doi = 10.1007/BF01463665 | title = High-Temperature Oxidation and Spontaneous Combustion of Rare-Earth Metal Powders | journal = Combustion, Explosion, and Shock Waves | volume = 21 | issue = 6 | pages = 656 | year = 1985 | bibcode = 1985CESW...21..656I | s2cid = 93281866 }}</ref>

==References==
{{Reflist|30em}}

==Further reading==
*''Guide to the Elements – Revised Edition'', Albert Stwertka, (Oxford University Press; 1998) {{ISBN|0-19-508083-1}}

==External links==
{{Commons category|Ytterbium}}
{{Wiktionary}}

*[http://education.jlab.org/itselemental/ele070.html It's Elemental – Ytterbium]
*{{Cite EB1911|wstitle=Ytterbium|short=x}}
* [https://link.springer.com/referenceworkentry/10.1007%2F978-3-319-39193-9_144-2 Encyclopedia of Geochemistry - Ytterbium]

{{Periodic table (navbox)}}
{{Ytterbium compounds}}
{{Authority control}}
{{Good article}}

[[Category:Ytterbium| ]]
[[Category:Chemical elements]]
[[Category:Chemical elements with face-centered cubic structure]]
[[Category:Lanthanides]]
[[Category:Suspected teratogens]]