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| {{infobox livermorium}}
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| '''Livermorium''' is the [[synthetic element|synthetic]] [[superheavy element]] with the symbol '''Lv''' and [[atomic number]] 116. The name was adopted by [[International Union of Pure and Applied Chemistry|IUPAC]] on May 30, 2012.<ref name="IUPAC-names-114-116">{{cite web | url = http://www.iupac.org/news/news-detail/article/element-114-is-named-flerovium-and-element-116-is-named-livermorium.html | title = Element 114 is Named Flerovium and Element 116 is Named Livermorium | publisher = [[International Union of Pure and Applied Chemistry|IUPAC]] | date = 30 May 2012}}</ref>
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| It is placed as the heaviest member of [[Chalcogen|group 16]] (VIA) although a sufficiently stable isotope is not known at this time to allow chemical experiments to confirm its position as a heavier [[homology (chemistry)|homologue]] to [[polonium]].
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| It was first detected in 2000. Since then, about 35 atoms of livermorium have been produced, either directly or as a decay product of [[ununoctium]], belonging to the four neighbouring isotopes with masses 290–293. The most stable isotope known is livermorium-293 with a [[half-life]] of ~60 ms.
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| ==History==
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| ===Unsuccessful synthesis attempts===
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| In late 1998, Polish physicist [[Robert Smolańczuk]] published calculations on the fusion of atomic nuclei towards the synthesis of [[superheavy element|superheavy atoms]], including ununoctium.<ref name=Smolanczuk>{{cite journal|author=Smolanczuk, R.|journal=[[Physical Review]] C|volume=59|issue=5|year=1999|title=Production mechanism of superheavy nuclei in cold fusion reactions|pages=2634–2639|doi=10.1103/PhysRevC.59.2634|bibcode = 1999PhRvC..59.2634S}}</ref> His calculations suggested that it might be possible to make [[ununoctium]] and livermorium by fusing [[lead]] with [[krypton]] under carefully controlled conditions.<ref name=Smolanczuk/>
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| In 1999, researchers at [[Lawrence Berkeley National Laboratory]] made use of these predictions and announced the discovery of livermorium and ununoctium, in a paper published in ''[[Physical Review Letters]]'',<ref name="Ninov83.1104">{{cite journal|last=Ninov|first=Viktor|last2=Gregorich|first2=K.|last3=Loveland|first3=W.|last4=Ghiorso|first4=A.|last5=Hoffman|first5=D.|last6=Lee|first6=D.|last7=Nitsche|first7=H.|last8=Swiatecki|first8=W.|last9=Kirbach|first9=U.|first10=C. |last10=Laue|first11=J. |last11=Adams|first12=J. |last12=Patin|first13=D. |last13=Shaughnessy|first14=D. |last14=Strellis|first15=P. |last15=Wilk|title=Observation of Superheavy Nuclei Produced in the Reaction of {{SimpleNuclide|Link|Krypton|86}} with {{SimpleNuclide|Link|Lead|208}}|journal=[[Physical Review Letters]]|volume=83|pages=1104–1107|year=1999|doi=10.1103/PhysRevLett.83.1104|bibcode=1999PhRvL..83.1104N|issue=6 |display-authors=10}}</ref> and very soon after the results were reported in ''[[Science (journal)|Science]]''.<ref>{{cite journal|author=Service, R. F.|journal=Science|year=1999|volume=284|page=1751|doi=10.1126/science.284.5421.1751|title=Berkeley Crew Bags Element 118|issue=5421}}</ref> The researchers reported to have performed the [[nuclear reaction|reaction]]
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| :{{Nuclide|Krypton|86}} + {{Nuclide|Lead|208}} → {{Nuclide|Ununoctium|293}} + {{SubatomicParticle|link=yes|Neutron}}.
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| The following year, they published a retraction after researchers at other laboratories were unable to duplicate the results and the Berkeley lab itself was unable to duplicate them as well.<ref>{{cite news|url=http://enews.lbl.gov/Science-Articles/Archive/118-retraction.html|publisher=Berkeley Lab|author=Public Affairs Department |title=Results of element 118 experiment retracted|date=2001-07-21|accessdate=2008-01-18}}</ref> In June 2002, the director of the lab announced that the original claim of the discovery of these two elements had been based on data fabricated by principal author [[Victor Ninov]].<ref>{{cite journal|pages=728–729|title=Misconduct: The stars who fell to Earth|journal=[[Nature (journal)|Nature]]|volume=420|doi=10.1038/420728a|year=2002|pmid=12490902|last1=Dalton|first1=R|issue=6917|bibcode = 2002Natur.420..728D }}</ref><ref>[http://physicsworld.com/cws/article/news/2629 Element 118 disappears two years after it was discovered]. Physicsworld.com. Retrieved on 2012-04-02.</ref>
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| ===Discovery===
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| On July 19, 2000, scientists at [[Dubna]] ([[Joint Institute for Nuclear Research|JINR]]) detected a single decay from an atom of livermorium following the irradiation of a [[Curium|Cm]]-248 target with [[Calcium|Ca]]-48 ions. The results were published in December 2000.<ref name=00Og01>{{cite journal|doi=10.1103/PhysRevC.63.011301|title=Observation of the decay of ^{292}116|year=2000|author=Oganessian, Yu. Ts.|journal=Physical Review C|volume=63|pages=011301|bibcode=2001PhRvC..63a1301O}}</ref> This 10.54 MeV alpha-emitting activity was originally assigned to <sup>292</sup>Lv due to the correlation of the daughter to previously assigned <sup>288</sup>Fl. That assignment was later altered to <sup>289</sup>Fl, and hence this activity was correspondingly changed to <sup>293</sup>Lv. Two further atoms were reported by the institute during their second experiment between April–May 2001.<ref name=03Pa01>[https://e-reports-ext.llnl.gov/pdf/302186.pdf "Confirmed results of the <sup>248</sup>Cm(<sup>48</sup>Ca,4n)<sup>292</sup>116 experiment"], ''Patin et al.'', ''LLNL report (2003)''. Retrieved 2008-03-03</ref>
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| :<math>\,^{48}_{20}\mathrm{Ca} + \,^{248}_{96}\mathrm{Cm} \to \,^{296}_{116}\mathrm{Lv} ^{*} \to \,^{293}_{116}\mathrm{Lv} + 3\,^{1}_{0}\mathrm{n}</math>
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| In the same experiment they also detected a decay chain which corresponded to the first observed decay of [[flerovium]] and assigned to <sup>289</sup>Fl.<ref name=03Pa01/>
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| This activity has not been observed again in a repeat of the same reaction. However, its detection in this series of experiments indicates the possibility of the decay of an isomer of livermorium, namely <sup>293b</sup>Lv, or a rare decay branch of the already discovered isomer,<sup>293a</sup>Lv, in which the first [[alpha particle]] was missed. Further research is required to positively assign this activity.
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| The team repeated the experiment in April–May 2005 and detected 8 atoms of livermorium. The measured decay data confirmed the assignment of the discovery [[isotope]] as <sup>293</sup>Lv. In this run, the team also observed <sup>292</sup>Lv in the 4n channel for the first time.<ref name=04Og01>{{cite doi|10.1103/PhysRevC.70.064609}}</ref>
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| In May 2009, the Joint Working Party reported on the discovery of [[copernicium]] and acknowledged the discovery of the isotope <sup>283</sup>Cn.<ref>{{cite journal|journal = [[Pure Appl. Chem.]]|year = 2009|title = Discovery of the element with atomic number 112|format = IUPAC Technical Report|author = R.C.Barber; H.W.Gaeggeler;P.J.Karol;H. Nakahara; E.Verdaci; E. Vogt|url = http://media.iupac.org/publications/pac/asap/pdf/PAC-REP-08-03-05.pdf|doi = 10.1351/PAC-REP-08-03-05|volume = 81|pages = 1331|issue = 7}}</ref> This implied the ''de facto'' discovery of livermorium, as <sup>291</sup>Lv (see below), from the acknowledgment of the data relating to the granddaughter <sup>283</sup>Cn, although the actual discovery experiment may be determined as that above.
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| In 2011, the IUPAC evaluated the Dubna team results and accepted them as a reliable identification of element 116.<ref name=jwr>{{cite journal|doi=10.1351/PAC-REP-10-05-01|title=Discovery of the elements with atomic numbers greater than or equal to 113 (IUPAC Technical Report)|year=2011|last1=Barber|first1=Robert C.|last2=Karol|first2=Paul J.|last3=Nakahara|first3=Hiromichi|last4=Vardaci|first4=Emanuele|last5=Vogt|first5=Erich W.|journal=Pure and Applied Chemistry|pages=1|volume=83|issue=7}}</ref>
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| ===Naming===
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| Livermorium is historically known as ''[[Mendeleev's predicted elements|eka]]-[[polonium]]''.<ref>[http://iopscience.iop.org/1402-4896/10/A/001/pdf/1402-4896_10_A_001.pdf The Search for New Elements: the Projects of Today in a Larger Perspective]</ref> ''Ununhexium'' (Uuh) was the temporary [[IUPAC]] [[systematic element name]]. Scientists usually refer to the element simply as ''element 116'' (or E116). According to IUPAC recommendations, the discoverer or discoverers of a new element have the right to suggest a name.<ref>{{cite journal|doi=10.1351/pac200274050787|url=http://media.iupac.org/publications/pac/2002/pdf/7405x0787.pdf|title=Naming of new elements(IUPAC Recommendations 2002)|year=2002|author=Koppenol, W. H.|journal=Pure and Applied Chemistry|volume=74|pages=787|issue=5}}</ref>
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| The discovery of livermorium was recognized by the Joint Working Group (JWG) of IUPAC on 1 June 2011, along with that of [[flerovium]].<ref name=jwr>{{cite journal|author=Barber, Robert C.; Karol, Paul J; Nakahara, Hiromichi; Vardaci, Emanuele; Vogt, Erich W.|title=Discovery of the elements with atomic numbers greater than or equal to 113 (IUPAC Technical Report)|doi=10.1351/PAC-REP-10-05-01|journal=Pure Appl. Chem.|year=2011|volume=83|issue=7|pages=1485}}</ref> According to the vice-director of JINR, the Dubna team wanted to name element 116 ''moscovium'', after the [[Moscow Oblast]] in which Dubna is located.<ref name="E114&116">{{cite web|publisher=rian.ru|year=2011|accessdate=2011-05-08|url=http://www.rian.ru/science/20110326/358081075.html|title=Russian Physicists Will Suggest to Name Element 116 Moscovium}}: Mikhail Itkis, the vice-director of JINR stated: "We would like to name element 114 after [[Georgy Flerov]] – flerovium, and another one [element 116] – moscovium, not after Moscow, but after [[Moscow Oblast]]".</ref> However, the name ''livermorium'' and the symbol ''Lv'' were adopted on May 31, 2012<ref name="IUPAC-names-114-116"/> after an approval process by the IUPAC.<ref name=IUPAC>{{cite web|title=News: Start of the Name Approval Process for the Elements of Atomic Number 114 and 116|url=http://www.iupac.org/news/news-detail/article/start-of-the-name-approval-process-for-the-elements-of-atomic-number-114-and-116.html|work=International Union of Pure and Applied Chemistry|accessdate=22 February 2012}}</ref> The name recognises the [[Lawrence Livermore National Laboratory]], within the city of [[Livermore, California]], USA, which collaborated with JINR on the discovery. The city in turn is named after the American rancher [[Robert Livermore]], a naturalized Mexican citizen of English birth.
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| ===Current and future experiments===
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| The team at Dubna have indicated plans to synthesize livermorium using the reaction between [[plutonium]]-244 and titanium-50. This experiment will allow them to assess the feasibility of using projectiles with Z > 20 required in the synthesis of superheavy elements in the [[period 8 element|eighth period]] (Z > 118). Although initially scheduled for 2008, the reaction looking at the synthesis of evaporation residues has not been conducted to date.<ref>[http://flerovlab.jinr.ru/flnr/programme_synth_2008.html Flerov Lab.]</ref>
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| There are also plans to repeat the Cm-248 reaction at different projectile energies in order to probe the 2n channel, leading to the new [[isotope]] <sup>294</sup>Lv. In addition, they have future plans to complete the [[excitation function]] of the 4n channel product, <sup>292</sup>Lv, which will allow them to assess the stabilizing effect of the N=184 shell on the yield of evaporation residues.
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| ==Nucleosynthesis==
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| ;Target-projectile combinations leading to Z=116 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 atomic number 116. ''The table below provides cross-sections and excitation energies for hot fusion reactions producing livermorium isotopes directly. Data in bold represent maxima derived from excitation function measurements. The below table contains various targets-projectile combinations for which calculations have provided estimates for cross section yields from various neutron evaporation channels.''
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| {|class="wikitable" style="text-align:center"
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| ! Target !! Projectile !! CN !! Attempt result
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| !<sup>208</sup>Pb
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| |<sup>82</sup>Se || <sup>290</sup>Lv<ref name=FengColdFusion >{{cite journal|arxiv=0707.2588|doi=10.1103/PhysRevC.76.044606|title=Formation of superheavy nuclei in cold fusion reactions|year=2007|author=Feng, Zhao-Qing|journal=Physical Review C|volume=76|pages=044606|last2=Jin|first2=Gen-Ming|last3=Li|first3=Jun-Qing|last4=Scheid|first4=Werner|bibcode=2007PhRvC..76d4606F|issue=4}}</ref>||{{no|Failure to date}}
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| !<sup>232</sup>Th
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| |<sup>58</sup>Fe || <sup>290</sup>Lv||{{unk|Reaction yet to be attempted}}
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| !<sup>238</sup>U
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| |<sup>54</sup>Cr||<sup>292</sup>Lv<ref name=FengHotFusion >{{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>||{{no|Failure to date}}
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| !<sup>244</sup>Pu
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| |<sup>50</sup>Ti||<sup>294</sup>Lv||{{unk|Reaction yet to be attempted}}
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| !<sup>248</sup>Cm
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| |<sup>48</sup>Ca||<sup>296</sup>Lv<ref name=04Og01/><ref name=FengHotFusion />||{{yes|Successful reaction}}
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| !<sup>246</sup>Cm
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| |<sup>48</sup>Ca||<sup>294</sup>Lv<ref name=04Og01/><ref name=FengHotFusion />||{{unk|Reaction yet to be attempted}}
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| !<sup>245</sup>Cm
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| |<sup>48</sup>Ca||<sup>293</sup>Lv<ref name=04Og02/><ref name=FengHotFusion />||{{yes|Successful reaction}}
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| !<sup>249</sup>Cf
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| |<sup>40</sup>Ar||<sup>289</sup>Lv||{{unk|Reaction yet to be attempted}}
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| |}
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| ===Cold fusion===
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| ;<sup>208</sup>Pb(<sup>82</sup>Se,''x''n)<sup>290−''x''</sup>Lv
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| In 1998, the team at GSI attempted the synthesis of <sup>290</sup>Lv as a radiative capture (''x''=0) product. No [[atoms]] were detected providing a cross section limit of 4.8 pb.
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| ===Hot fusion===
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| ''This section deals with the synthesis of nuclei of livermorium by so-called "hot" fusion reactions. These are processes which create compound nuclei at high excitation energy (~40–50 MeV, hence "hot"), leading to a reduced probability of survival from fission. The excited nucleus then decays to the ground state via the emission of 3–5 neutrons. Fusion reactions utilizing <sup>48</sup>Ca nuclei usually produce compound nuclei with intermediate excitation energies (~30–35 MeV) and are sometimes referred to as "warm" fusion reactions. This leads, in part, to relatively high yields from these reactions.''
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| ;<sup>238</sup>U(<sup>54</sup>Cr,''x''n)<sup>292−''x''</sup>Lv
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| There are sketchy indications that this reaction was attempted by the team at GSI in 2006. There are no published results on the outcome, presumably indicating that no atoms were detected. This is expected from a study of the systematics of cross sections for <sup>238</sup>U targets.<ref>[http://opal.dnp.fmph.uniba.sk/~beer/experiments.php "List of experiments 2000–2006"]</ref>
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| ;<sup>248</sup>Cm(<sup>48</sup>Ca,''x''n)<sup>296−''x''</sup>Lv (''x''=3,4)
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| The first attempt to synthesise livermorium was performed in 1977 by Ken Hulet and his team at the Lawrence Livermore National Laboratory (LLNL). They were unable to detect any atoms of livermorium.<ref>{{cite journal|doi=10.1103/PhysRevLett.39.385|title=Search for Superheavy Elements in the Bombardment of <sup>248</sup>Cm with <sup>48</sup>Ca|year=1977|author=Hulet, E. K.|journal=Physical Review Letters|volume=39|pages=385|last2=Lougheed|first2=R.|last3=Wild|first3=J.|last4=Landrum|first4=J.|last5=Stevenson|first5=P.|last6=Ghiorso|first6=A.|last7=Nitschke|first7=J.|last8=Otto|first8=R.|last9=Morrissey|first9=D.|first10=P. |last10=Baisden|first11=B. |last11=Gavin|first12=D. |last12=Lee|first13=R. |last13=Silva|first14=M. |last14=Fowler|first15=G. |last15=Seaborg|bibcode=1977PhRvL..39..385H|issue=7}}</ref> Yuri Oganessian and his team at the Flerov Laboratory of Nuclear Reactions (FLNR) subsequently attempted the reaction in 1978 and were met by failure. In 1985, a joint experiment between Berkeley and Peter Armbruster's team at GSI, the result was again negative with a calculated cross-section limit of 10–100 pb.<ref>{{cite journal|doi=10.1103/PhysRevLett.54.406|title=Attempts to Produce Superheavy Elements by Fusion of 48Ca with 248Cm in the Bombarding Energy Range of 4.5–5.2 MeV/u|year=1985|author=Armbruster, P.|journal=Physical Review Letters|volume=54|pages=406–409|pmid=10031507|last2=Agarwal|first2=YK|last3=Brüchle|first3=W|last4=Brügger|first4=M|last5=Dufour|first5=JP|last6=Gaggeler|first6=H|last7=Hessberger|first7=FP|last8=Hofmann|first8=S|last9=Lemmertz|first9=P|first10=G |last10=Münzenberg
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| |first11=K |last11=Poppensieker|first12=W |last12=Reisdorf|first13=M |last13=Schädel
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| |first14=KH |last14=Schmidt|first15=JHR |last15=Schneider|first16=WFW |last16=Schneider|first17=K |last17=Sümmerer|first18=D |last18=Vermeulen|first19=G |last19=Wirth|first20=A |last20=Ghiorso|first21=KE |last21=Gregorich|first22=D |last22=Lee|first23=M |last23=Leino|first24=KJ |last24=Moody|first25=GT |last25=Seaborg|first26=RB |last26=Welch|first27=P |last27=Wilmarth|first28=S |last28=Yashita|first29=C |last29=Frink|first30=N |last30=Greulich|first31=G |last31=Herrmann|first32=U |last32=Hickmann|first33=N |last33=Hildebrand|first34=JV |last34=Kratz|first35=N |last35=Trautmann|first36=MM |last36=Fowler|first37=DC |last37=Hoffman
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| |first38=WR |last38=Daniels|first39=HR |last39=von Gunten|first40=H |last40=Dornhöfer|issue=5|bibcode=1985PhRvL..54..406A|display-authors=10}}</ref>
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| In 2000, Russian scientists at Dubna finally succeeded in detecting a single atom of livermorium, assigned to the isotope <sup>292</sup>Lv.<ref name=00Og01/>
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| In 2001, they repeated the reaction and formed a further 2 atoms in a confirmation of their discovery experiment. A third atom was tentatively assigned to <sup>293</sup>Lv on the basis of a missed parental alpha decay.<ref name=03Pa01/>
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| In April 2004, the team ran the experiment again at higher energy and were able to detect a new decay chain, assigned to <sup>292</sup>Lv. On this basis, the original data were reassigned to <sup>293</sup>Lv. The tentative chain is therefore possibly associated with a rare decay branch of this isotope. In this reaction, 2 further atoms of <sup>293</sup>Lv were detected.<ref name=04Og01/>
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| In an experiment run at the GSI between June-July 2010, scientists detected six atoms of livermorium; two atoms of <sup>293</sup>116 and four atoms of <sup>292</sup>116. They were able to confirm both the decay data and cross sections for the fusion reaction.
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| ;<sup>245</sup>Cm(<sup>48</sup>Ca,xn)<sup>293−x</sup>116 (x=2,3)
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| In order to assist in the assignment of isotope mass numbers for livermorium, in March–May 2003 the Dubna team bombarded a <sup>245</sup>Cm target with <sup>48</sup>Ca ions. They were able to observe two new isotopes, assigned to <sup>291</sup>Lv and <sup>290</sup>Lv.<ref name=04Og02>{{cite doi|10.1103/PhysRevC.69.054607}}</ref> This experiment was successfully repeated in Feb–March 2005 where 10 atoms were created with identical decay data to those reported in the 2003 experiment.<ref name=06og01>{{cite journal|title=Synthesis of the isotopes of elements 118 and 116 in the <sup>249</sup>Cf and <sup>245</sup>Cm+<sup>48</sup>Ca fusion reactions|author1=<Please add first missing authors to populate metadata.>}}</ref>
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| ===As decay product===
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| Livermorium has also been observed in the decay of ununoctium. In October 2006 it was announced that 3 atoms of [[ununoctium]] had been detected by the bombardment of [[californium]]-249 with calcium-48 ions, which then rapidly decayed into livermorium.<ref name=06og01/>
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| The observation of <sup>290</sup>Lv allowed the assignment of the product to <sup>294</sup>Uuo and proved the synthesis of [[ununoctium]].
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| ===Fission of compound nuclei with Z=116===
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| Several experiments have been performed between 2000–2006 at the Flerov laboratory of Nuclear Reactions in Dubna studying the fission characteristics of the compound nuclei <sup>296,294,290</sup>Lv. Four nuclear reactions have been used, namely <sup>248</sup>Cm+<sup>48</sup>Ca, <sup>246</sup>Cm+<sup>48</sup>Ca, <sup>244</sup>Pu+<sup>50</sup>Ti and <sup>232</sup>Th+<sup>58</sup>Fe. The results have revealed how nuclei such as this fission predominantly by expelling closed shell nuclei such as <sup>132</sup>Sn (Z=50, N=82). It was also found that the yield for the fusion-fission pathway was similar between <sup>48</sup>Ca and <sup>58</sup>Fe projectiles, indicating a possible future use of <sup>58</sup>Fe projectiles in superheavy element formation. In addition, in comparative experiments synthesizing <sup>294</sup>Lv using <sup>48</sup>Ca and <sup>50</sup>Ti projectiles, the yield from fusion-fission was ~3x less for <sup>50</sup>Ti, also suggesting a future use in SHE production.<ref>see [http://www1.jinr.ru/Reports/Reports_eng_arh.html Flerov lab annual reports 2000–2006]</ref>
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| ==Isotopes and nuclear properties==
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| ;Chronology of isotope discovery
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| {|class="wikitable" style="text-align:center"
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| !Isotope!!Year discovered!!Discovery reaction
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| |<sup>290</sup>Lv||2002||<sup>249</sup>Cf(<sup>48</sup>Ca,3n)<ref>see [[ununoctium]]</ref>
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| |-
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| |<sup>291</sup>Lv||2003||<sup>245</sup>Cm(<sup>48</sup>Ca,2n)<ref name=04Og02/>
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| |-
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| |<sup>292</sup>Lv||2004||<sup>248</sup>Cm(<sup>48</sup>Ca,4n)<ref name=04Og01/>
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| |-
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| |<sup>293</sup>Lv||2000||<sup>248</sup>Cm(<sup>48</sup>Ca,3n)<ref name=00Og01/>
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| |}
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| Theoretical calculation in a quantum tunneling model supports the experimental data relating to the synthesis of <sup>293,292</sup>Lv.<ref name=half-lifes>{{cite journal|journal=Phys. Rev. C|volume=73|pages=014612|year=2006|title=α decay half-lives of new superheavy elements|author=P. Roy Chowdhury, C. Samanta, and D. N. Basu|doi=10.1103/PhysRevC.73.014612|bibcode=2006PhRvC..73a4612C|arxiv = nucl-th/0507054 }}</ref><ref>{{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=C. Samanta, P. Roy Chowdhury and D.N. Basu|doi=10.1016/j.nuclphysa.2007.04.001|bibcode=2007NuPhA.789..142S|arxiv = nucl-th/0703086 }}</ref>
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| ;Retracted isotope: <sup>289</sup>Lv
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| In 1999, researchers at [[Lawrence Berkeley National Laboratory]] announced the synthesis of <sup>293</sup>Uuo (see [[ununoctium]]), in a paper published in ''Physical Review Letters''.<ref name="Ninov83.1104"/> The claimed isotope <sup>289</sup>Lv decayed by 11.63 MeV alpha emission with a half-life of 0.64 ms. The following year, they published a [[retraction]] after other researchers were unable to duplicate the results.<ref>{{cite journal|doi=10.1103/PhysRevLett.89.039901|title=Editorial Note: Observation of Superheavy Nuclei Produced in the Reaction of <sup>86</sup>Kr with <sup>208</sup>Pb [Phys. Rev. Lett. 83, 1104 (1999)]|year=2002|author=Ninov, V.|journal=Physical Review Letters|volume=89|pages=039901|bibcode=2002PhRvL..89c9901N|last2=Gregorich|first2=K.|last3=Loveland|first3=W.|last4=Ghiorso|first4=A.|last5=Hoffman|first5=D.|last6=Lee|first6=D.|last7=Nitsche|first7=H.|last8=Swiatecki|first8=W.|last9=Kirbach|first9=U.|first10=C. |last10=Laue|first11=J. |last11=Adams|first12=J. |last12=Patin|first13=D. |last13=Shaughnessy|first14=D. |last14=Strellis|first15=P. |last15=Wilk|issue=3 |display-authors=10}}</ref> In June 2002, the director of the lab announced that the original claim of the discovery of these two elements had been based on data fabricated by the principal author [[Victor Ninov]]. As such, this isotope of livermorium is currently unknown.
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| ==Chemical properties==
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| ===Extrapolated chemical properties===
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| ====Oxidation states====
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| Livermorium is projected to be the fourth member of the 7p series of [[non-metal]]s and the heaviest member of group 16 (VIA) in the Periodic Table, below [[polonium]]. The group oxidation state of +6 is known for all the members apart from oxygen which lacks available d-[[Atomic orbital|orbitals]] for expansion and is limited to a maximum +2 state, exhibited in the fluoride OF<sub>2</sub>. The +4 is known for [[sulfur]], [[selenium]], [[tellurium]], and polonium, undergoing a shift in stability from reducing for S(IV) and Se(IV) to oxidizing in Po(IV). Tellurium(IV) is the most stable for this element. This suggests a decreasing stability for the higher oxidation states as the group is descended and livermorium should portray an oxidizing +4 state and a more stable +2 state. The lighter members are also known to form a −2 state as [[oxide]], [[sulfide]], [[selenide]], [[telluride (chemistry)|telluride]], and [[polonide]].
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| ====Chemistry====
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| The possible chemistry of livermorium can be extrapolated from that of [[polonium]]. It should therefore undergo [[oxidation]] to a dioxide, LvO<sub>2</sub>, although a trioxide, LvO<sub>3</sub> is plausible, but unlikely. The stability of a +2 state should manifest itself in the formation of a simple monoxide, LvO. [[Fluorination]] will likely result in a tetrafluoride, LvF<sub>4</sub> and/or a difluoride, LvF<sub>2</sub>; a [[hexafluoride]], LvF<sub>6</sub>, is possible but unlikely. [[halogenation|Chlorination]] and [[bromination]] may well stop at the corresponding dihalides, LvCl<sub>2</sub> and LvBr<sub>2</sub>. [[Oxidation]] by [[iodine]] should certainly stop at LvI<sub>2</sub> and may even be [[inert]] to this element.{{Citation needed|date=May 2009}} The heavier livermorium dihalides are predicted to be [[linear molecular geometry|linear]], but the lighter ones are predicted to be [[bent molecular geometry|bent]].<ref>{{cite doi|10.1063/1.2711197}}</ref>
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| ==See also==
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| * [[Island of stability]]
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| {{clear}}
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| ==References==
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| {{Reflist|colwidth=30em}}
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| ==External links==
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| {{Commons|Livermorium}}
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| * [http://www.periodicvideos.com/videos/116.htm Livermorium] at ''[[The Periodic Table of Videos]]'' (University of Nottingham)
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| * [http://cerncourier.com/main/article/41/8/17 ''CERN Courier'' – Second postcard from the island of stability]
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| * [http://webelements.com/livermorium/ Livermorium at WebElements.com]
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| {{compact periodic table}}
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| {{Chemical elements named after places}}
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| [[Category:Chalcogens]]
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| [[Category:Chemical elements]]
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| [[Category:Synthetic elements]]
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| [[Category:Livermorium]]
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