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| {{Infobox ununennium}}
| | My name is Wilfredo Norcross. I life in Bergen (Norway).<br><br>my website ... [https://itunes.apple.com/us/artist/arthur-falcone/id314222640 arthur falcone] |
| '''Ununennium''', also known as '''[[Mendeleev's predicted elements|eka]]-[[francium]]''' or element 119, is the temporary name of a [[chemical element]] in the [[periodic table]] that has the temporary symbol '''Uue''' and has the [[atomic number]] 119. To date, attempted syntheses of this element have been unsuccessful. Since it is below the [[alkali metals]] it might have properties similar to those of [[francium]] or [[caesium]] and thus be extremely reactive with water and air (though [[relativistic quantum chemistry|relativistic effects]] might make it less reactive than francium and caesium). A predicted oxidation state is +1; however, unlike all the other alkali metals, it is also predicted to show the +3 oxidation state.
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| Ununennium would be the first element in the eighth [[periodic table period|period]] of the [[periodic table]].
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| ==Attempts at synthesis==
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| The synthesis of ununennium was attempted in 1985 by bombarding a target of [[einsteinium]]-254 with [[calcium]]-48 ions at the superHILAC accelerator at Berkeley, California:
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| :<math>\,^{254}_{99}\mathrm{Es} + \,^{48}_{20}\mathrm{Ca} \to \,^{302}_{119}\mathrm{Uue} ^{*} </math>
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| No atoms were identified, leading to a limiting yield of 300 [[barn (unit)|nb]].<ref>{{cite journal|title=Search for superheavy elements using <sup>48</sup>Ca + <sup>254</sup>Es<sup>g</sup> reaction|journal=Physical Reviews C|year=1985|pages=1760–1763|doi=10.1103/PhysRevC.32.1760|volume=32|issue=5|bibcode = 1985PhRvC..32.1760L|last1=Lougheed|first1=R.|last2=Landrum|first2=J.|last3=Hulet|first3=E.|last4=Wild|first4=J.|last5=Dougan|first5=R.|last6=Dougan|first6=A.|last7=Gäggeler|first7=H.|last8=Schädel|first8=M.|last9=Moody|first9=K. |displayauthors=11}}</ref>
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| As of May 2012, plans are under way to attempt to synthesize the isotopes <sup>295</sup>Uue and <sup>296</sup>Uue by bombarding a target of [[berkelium]] with [[titanium]] at the [[GSI Helmholtz Centre for Heavy Ion Research]] in [[Darmstadt]], Germany:<ref name="economist">[http://www.economist.com/node/21554502 Modern alchemy: Turning a line], [[The Economist]], May 12, 2012.</ref><ref>Düllmann, Christoph E. (October 20, 2011). [http://fias.uni-frankfurt.de/kollo/Duellmann_FIAS-Kolloquium.pdf Superheavy Element Research: News from GSI and Mainz]. Johannes Gutenberg University Mainz; GSI Helmholtzzentrum für Schwerionenforschung GmbH; Darmstadt Helmholtz Institute Mainz.</ref>
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| :<math>\,^{249}_{97}\mathrm{Bk} + \,^{50}_{22}\mathrm{Ti} \to \,^{296}_{119}\mathrm{Uue} \,+3\,^{1}_{0}\mathrm{n}</math>
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| :<math>\,^{249}_{97}\mathrm{Bk} + \,^{50}_{22}\mathrm{Ti} \to \,^{295}_{119}\mathrm{Uue} \,+4\,^{1}_{0}\mathrm{n}</math>
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| ==Predicted decay characteristics==
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| The alpha-decay half-lives of 1700 nuclei with 100 ≤ Z ≤ 130 have been calculated in a quantum tunneling model with alpha-decay Q-values from different mass estimates.<ref name=npa07>{{cite journal|journal=Nucl. Phys. A|volume=789|pages=142–154|year=2007|title=Predictions of alpha decay half lives of heavy and superheavy elements|author=Chowdhury, P. Roy; Samanta, C. and Basu, D. N. |doi=10.1016/j.nuclphysa.2007.04.001|bibcode=2007NuPhA.789..142S|arxiv = nucl-th/0703086 }}</ref><ref>{{cite journal|journal=Phys. Rev. C|volume=77|pages=044603|year=2008|title=Search for long lived heaviest nuclei beyond the valley of stability|author=Chowdhury, P. Roy; Samanta, C. and Basu, D. N. |doi=10.1103/PhysRevC.77.044603|issue=4|bibcode=2008PhRvC..77d4603C|arxiv = 0802.3837 }}</ref><ref>{{cite journal|journal=At. Data & Nucl. Data Tables|volume=94|pages=781–806|year=2008|title=Nuclear half-lives for α -radioactivity of elements with 100 ≤ Z ≤ 130|author=Chowdhury, P. Roy; Samanta, C. and Basu, D. N. |doi=10.1016/j.adt.2008.01.003|issue=6|bibcode=2008ADNDT..94..781C|arxiv = 0802.4161 }}</ref> The alpha-decay half-lives predicted for <sup>291–307</sup>119 are of the order of micro-seconds. The highest value of the alpha-decay half-life predicted in the quantum tunneling model with the mass estimates from a macroscopic-microscopic model is ~485 microseconds for the isotope <sup>294</sup>119. For <sup>302</sup>119 it is ~163 microseconds.
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| ==Target-projectile combinations leading to Z=119 compound nuclei==
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| The below table contains various combinations of targets and projectiles which could be used to form compound nuclei with an atomic number of 119.
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| {|class="wikitable" style="text-align:center"
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| !Target!!Projectile!!CN!!Attempt result
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| !<sup>254</sup>Es
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| |<sup>48</sup>Ca||<sup>302</sup>Uue||{{no|Failure to date}}
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| |-
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| !<sup>249</sup>Bk
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| |<sup>50</sup>Ti||<sup>299</sup>Uue||{{unk|Planned reaction}}
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| |}<!--Please use {{yes|Successful reaction}} for successes, thanks-->
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| ==Theoretical calculations on evaporation cross sections==
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| The below table contains various targets-projectile combinations for which calculations have provided estimates for cross section yields from various neutron evaporation channels. The channel with the highest expected yield is given.
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| DNS = Di-nuclear system; σ = cross section
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| {|class="wikitable" style="text-align:center"
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| !Target!!Projectile!!CN!!Channel (product)!!σ <sub>max</sub>!!Model!!Ref
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| !<sup>254</sup>Es
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| |<sup>48</sup>Ca||<sup>302</sup>Uue||3n (<sup>299</sup>Uue)||0.5 pb||DNS||<ref>{{cite journal|arxiv=0803.1117|doi=10.1016/j.nuclphysa.2008.11.003|title=Production of heavy and superheavy nuclei in massive fusion reactions|year=2009|author=Feng, Z|journal=Nuclear Physics A|volume=816|page=33|last2=Jin|first2=G|last3=Li|first3=J|last4=Scheid|first4=W|bibcode=2009NuPhA.816...33F}}</ref>
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| |}
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| ==Extrapolated chemical properties==
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| Ununennium is expected to behave normally for an alkali metal and exhibit a strong +1 [[oxidation state]]. However, the energetic properties of its [[valence electron]] would increase its first [[ionization energy]], making it less reactive than expected and more like [[potassium]] than [[caesium]] chemically. This would also decrease the [[metallic radius|metallic]] and [[ionic radius|ionic radii]] of ununennium.<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> Ununennium is also predicted to be the first alkali metal to display the +3 oxidation state, due to the ionization energy of the 7p<sub>3/2</sub> electrons, which is predicted to be very low.<ref name=Haire/>
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| ==See also==
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| *[[Extended periodic table]]
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| ==References==
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| {{clear}}
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| {{Reflist|colwidth=30em}}
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| {{Compact extended periodic table}}
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| [[Category:Chemical elements]]
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| [[Category:Alkali metals]]
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| [[Category:Hypothetical chemical elements]]
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My name is Wilfredo Norcross. I life in Bergen (Norway).
my website ... arthur falcone