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| {{Infobox unbihexium}}
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| '''Unbihexium''' is the temporary name of an undiscovered [[superheavy element|superheavy]] [[chemical element]] with temporary symbol '''Ubh''' and [[atomic number]] 126. The element, also known as '''[[Mendeleev's predicted elements|eka]]'''-'''[[plutonium]]''' or simply '''element 126''', is predicted to be near the centre of the hypothesized [[island of stability]], and thus may have a very long half-life, much greater than what would be predicted without the island of stability. Because of this, it has attracted interest from researchers trying to synthesize it.
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| ==History==
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| ===Synthesis===
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| The first and only attempt to synthesize unbihexium, which was unsuccessful, was performed in 1971 at [[CERN]] by [[René Bimbot]] and John M. Alexander<!--don't link; the article titled "John M. Alexander" goes to a different John M. Alexander--> using the hot fusion reaction:<ref name="emsley"/>
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| : {{nuclide2|thorium|232|link=y}} + {{nuclide2|krypton|84|link=y}} → {{nuclide2|unbihexium|316}}* → ''no atoms''<!-- please, drop the attitude to use the resource-consuming <math> for any (non-mathematical) crap which one cannot easily type-as-it-reads on an en-US keyboard. learn templates, HTML and Unicode -->
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| A high energy [[alpha particle]] was observed and taken as possible evidence for the synthesis of unbihexium. Recent research{{which|date=October 2011}} suggests that this is highly unlikely as the sensitivity of experiments performed in 1971 would have been several orders of magnitude too low according to current understanding.
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| Another way to synthesize unbihexium would be to overshoot it by fusion of <sup>130</sup>[[tellurium|Te]] and <sup>204</sup>[[mercury (element)|Hg]]; successive alpha decay of the compound nucleus {{su|p=334|b=132}}Utb would land right on <sup>322</sup>Ubh (predicted to be relatively stable). <sup>130</sup>Te constitutes about 34% of natural tellurium; however, <sup>204</sup>Hg only constitutes about 7% of natural mercury. This method of synthesis could also be used to synthesize <sup>298</sup>[[Flerovium|Fl]], after the alpha decay of <sup>322</sup>Ubh.{{citation needed|date=October 2013}}
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| ===Primordial unbihexium===
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| It was suggested in 1976 that [[primordial element|primordial]] superheavy elements (mainly [[livermorium]], [[unbiquadium]], unbihexium, and [[unbiseptium]]) could be a cause of unexplained radiation damage in minerals. This prompted many researchers to search for it in nature from 1976 to 1983. Some claimed that they had detected alpha particles with the right energies to cause the damage observed, supporting the presence of unbihexium, while some claimed that no unbihexium had been detected. However, the possible extent of primordial unbihexium on Earth is uncertain; it might now only exist in traces, or could even have completely decayed by now after having caused the radiation damage long ago.<ref name="emsley">{{cite book|last=Emsley|first=John|title=Nature's Building Blocks: An A-Z Guide to the Elements|edition=New|year=2011|publisher=Oxford University Press|location=New York, NY|isbn=978-0-19-960563-7|page=592}}</ref>
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| ==Naming==
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| Using [[Mendeleev's predicted elements|Mendeleev's nomenclature for unnamed and undiscovered elements]], unbihexium should be known as ''eka-[[plutonium]]'' or ''dvi-[[samarium]]''. In 1979 IUPAC published recommendations according to which the element was to be called ''unbihexium'' (with the corresponding symbol of ''Ubh''),<ref name=iupac>{{cite journal|author=Chatt, J.|journal=Pure Appl. Chem.|year=1979|volume=51|pages=381–384|title=Recommendations for the Naming of Elements of Atomic Numbers Greater than 100|doi=10.1351/pac197951020381|issue=2}}</ref> a [[systematic element name]] as a [[placeholder name|placeholder]], until the discovery of the element is confirmed and a name is decided on. The recommendations are largely ignored among scientists, who call it "element 126", with the symbol of ''(126)'' or even simply ''126''.<ref name="Haire">{{cite book| title = The Chemistry of the Actinide and Transactinide Elements| editor1-last = Morss|editor2-first = Norman M.| editor2-last = Edelstein| editor3-last = Fuger|editor3-first = Jean| last = Haire|first = Richard G.| chapter = Transactinides and the future elements| publisher = [[Springer Science+Business Media]]| year = 2006| page = 1724| isbn = 1-4020-3555-1| location = Dordrecht, The Netherlands| edition = 3rd| ref = CITEREFHaire2006}}</ref>
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| ==Predicted properties==
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| ===Nuclear stability and isotopes===
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| [[File:Island of Stability.svg|thumb|400px|alt=A 3D graph of stability of elements vs. number of protons Z and neutrons N, showing a "mountain chain" running diagonally through the graph from the low to high numbers, as well as an "island of stability" at high N and Z.|Unbihexium is predicted to lie near the peak of the "island of stability".<ref name="emsley"/>]]
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| {{see also|Island of stability}}
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| The stability of nuclei decreases greatly with the increase in atomic number after [[plutonium]], the heaviest [[primordial element]], so that all isotopes with an atomic number above [[mendelevium|101]] [[radioactive decay|decay radioactively]] with a [[half-life]] under a day, with an exception of [[dubnium]]-268. No elements with [[atomic number]]s above 82 (after [[lead]]) have stable isotopes.<ref>{{cite journal|last = Marcillac|first = Pierre de|coauthors = Noël Coron, Gérard Dambier, Jacques Leblanc, and Jean-Pierre Moalic|date=April 2003|title = Experimental detection of α-particles from the radioactive decay of natural bismuth|journal = Nature|volume = 422|pages = 876–878|pmid=12712201|doi = 10.1038/nature01541|issue = 6934|bibcode = 2003Natur.422..876D}}</ref> Nevertheless, because of [[magic number (physics)|reasons]] not very well understood yet, there is a slight increased nuclear stability around atomic numbers [[darmstadtium|110]]–[[flerovium|114]], which leads to the appearance of what is known in nuclear physics as the "[[island of stability]]". This concept, proposed by [[University of California, Berkeley|University of California]] professor [[Glenn Seaborg]], explains why [[superheavy element]]s last longer than predicted.<ref>{{cite book|title=Van Nostrand's scientific encyclopedia|first1=Glenn D. |last1= Considine |first2=Peter H. |last2= Kulik|publisher=Wiley-Interscience|year=2002|edition=9|isbn=978-0-471-33230-5|oclc=223349096}}</ref> Calculations according to the [[Hartree–Fock method|Hartree–Fock]]–Bogoliubov Method using the non-relativistic Skyrme interaction have proposed Z=126 as a [[nuclear shell model|closed proton shell]]. In this region of the periodic table, N=184 and N=196 have been suggested as [[nuclear shell model|closed neutron shell]]s. Therefore the isotopes of most interest are <sup>310</sup>Ubh and <sup>322</sup>Ubh, for these might be considerably longer-lived than other isotopes. Unbihexium, having a [[magic number (physics)|magic number]] of [[proton]]s, is predicted to be more stable than other elements in this region, and may have [[nuclear isomer]]s with very long [[half-life|half-lives]].<ref name="emsley"/>
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| ===Atomic and physical===
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| {{expand section|date=September 2012}}
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| Unbihexium is predicted to belong to a new block of [[Valence electron|valence]] g-electron atoms, although the g-block's position left of the [[f-block]] is speculative. The expected [[electron configuration]] is [[[Ununoctium|Uuo]]] 5g<sup>2</sup> 6f<sup>2</sup> 7d<sup>1</sup> 8s<sup>2</sup> 8p<sup>1</sup>,<ref name=Haire/> due to the expected smearing out of the energies of 5g, 6f, 7d and 8p orbitals.<ref name=EB>{{cite web|author=Seaborg|url=http://www.britannica.com/EBchecked/topic/603220/transuranium-element|title=transuranium element (chemical element)|publisher=Encyclopædia Britannica|date=c. 2006|accessdate=2010-03-16}}</ref>
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| ===Chemical===
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| Unbihexium is predicted to display a variety of [[oxidation state]]s, perhaps extending up to +8.<ref name="emsley"/> Recent calculations have suggested a stable [[Fluoride|monofluoride]] UbhF may be possible, resulting from a bonding interaction between the 5g [[Atomic orbital|orbital]] on Ubh and the 2[[p-orbital|p]] orbital on [[fluorine]].<ref>{{Cite journal|last=Jacoby|first=Mitch|title=As-yet-unsynthesized superheavy atom should form a stable diatomic molecule with fluorine|journal=Chemical & Engineering News|year=2006|volume=84|issue=10|pages=19|url=http://pubs.acs.org/cen/news/84/i10/8410notw9.html|accessdate=2008-01-14}}</ref> Other predicted oxidation states include III, IV, VI, and VIII.
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| ==References==
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| {{Reflist}}
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| {{Use dmy dates|date=September 2010}}
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| {{Compact extended periodic table}}
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| [[Category:Chemical elements]]
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| [[Category:Hypothetical chemical elements]]
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Friends contact her Felicidad and her spouse doesn't like it at all. Her family members lives in Idaho. To play handball is the thing she loves most of all. I am a manufacturing and distribution officer.
Also visit my blog post extended car warranty - their explanation -