Editing Livermorium (section)

== Predicted properties ==
Other than nuclear properties, no properties of livermorium or its compounds have been measured; this is due to its extremely limited and expensive production<ref name="Bloomberg">{{Cite news|url=https://www.bloomberg.com/news/features/2019-08-28/making-new-elements-doesn-t-pay-just-ask-this-berkeley-scientist|title=Making New Elements Doesn't Pay. Just Ask This Berkeley Scientist|last=Subramanian|first=S.|website=[[Bloomberg Businessweek]]|date=2019-08-28 |access-date=2020-01-18}}</ref> and the fact that it decays very quickly. Properties of livermorium remain unknown and only predictions are available.

=== Nuclear stability and isotopes ===
{{Main|Isotopes of livermorium}}
[[File:Island of Stability derived from Zagrebaev.svg|right|thumb|upright=1.8|The expected location of the island of stability is marked by the white circle. The dotted line is the line of [[beta decay|beta]] stability.]]
Livermorium is expected to be near an [[island of stability]] centered on [[copernicium]] (element 112) and [[flerovium]] (element 114).<ref name="Zagrebaev">{{cite conference |last1=Zagrebaev |first1=Valeriy |last2=Karpov |first2=Alexander |last3=Greiner |first3=Walter |date=2013 |title=Future of superheavy element research: Which nuclei could be synthesized within the next few years? |publisher=IOP Science |book-title=Journal of Physics: Conference Series |volume=420 |pages=1–15 |url=http://iopscience.iop.org/1742-6596/420/1/012001/pdf/1742-6596_420_1_012001.pdf |access-date=20 August 2013}}</ref><ref>{{cite book|title=Van Nostrand's scientific encyclopedia|first1=Glenn D. |last1= Considine |first2=Peter H. |last2= Kulik|publisher=Wiley-Interscience|date=2002|edition=9th|isbn=978-0-471-33230-5|oclc=223349096}}</ref> Due to the expected high [[fission barrier]]s, any nucleus within this island of stability exclusively decays by alpha decay and perhaps some electron capture and [[beta decay]].{{Fricke1975}} While the known isotopes of livermorium do not actually have enough neutrons to be on the island of stability, they can be seen to approach the island, as the heavier isotopes are generally the longer-lived ones.<ref name="00Og01" /><ref name="JWP" />

Superheavy elements are produced by [[nuclear fusion]]. These fusion reactions can be divided into "hot" and "cold" fusion,{{efn|Despite the name, "cold fusion" in the context of superheavy element synthesis is a distinct concept from the idea that nuclear fusion can be achieved in room temperature conditions (see [[cold fusion]]).<ref>{{cite journal |doi=10.1016/0022-0728(89)80006-3 |title=Electrochemically induced nuclear fusion of deuterium |date=1989 |last1=Fleischmann |first1=Martin |last2=Pons |first2=Stanley |journal=Journal of Electroanalytical Chemistry and Interfacial Electrochemistry |volume=261 |issue=2 |pages=301–308}}</ref>}} depending on the excitation energy of the compound nucleus produced. In hot fusion reactions, very light, high-energy projectiles are accelerated toward very heavy targets ([[actinide]]s), giving rise to compound nuclei at high excitation energy (~40–50&nbsp;[[electronvolt|MeV]]) that may either fission or evaporate several (3 to 5) neutrons.<ref name="fusion">{{cite journal |last1=Barber |first1=Robert C. |last2=Gäggeler |first2=Heinz W. |last3=Karol |first3=Paul J. |last4=Nakahara |first4=Hiromichi |last5=Vardaci |first5=Emanuele |last6=Vogt |first6=Erich |title=Discovery of the element with atomic number 112 (IUPAC Technical Report) |journal=Pure and Applied Chemistry |volume=81 |issue=7 |page=1331 |date=2009 |doi=10.1351/PAC-REP-08-03-05|s2cid=95703833 |url=http://doc.rero.ch/record/297412/files/pac-rep-08-03-05.pdf }}</ref> In cold fusion reactions (which use heavier projectiles, typically from the [[period 4 element|fourth period]], and lighter targets, usually [[lead]] and [[bismuth]]), the produced fused nuclei have a relatively low excitation energy (~10–20&nbsp;MeV), which decreases the probability that these products will undergo fission reactions. As the fused nuclei cool to the [[ground state]], they require emission of only one or two neutrons. Hot fusion reactions tend to produce more neutron-rich products because the actinides have the highest neutron-to-proton ratios of any elements that can presently be made in macroscopic quantities.<ref name="AM89">{{cite journal |first1=Peter |last1=Armbruster |name-list-style=amp |first2=Gottfried |last2=Münzenberg |title=Creating superheavy elements |journal=Scientific American |volume=34 |pages=36–42 |date=1989}}</ref>

Important information could be gained regarding the properties of superheavy nuclei by the synthesis of more livermorium isotopes, specifically those with a few neutrons more or less than the known ones – <sup>286</sup>Lv, <sup>287</sup>Lv, <sup>294</sup>Lv, and <sup>295</sup>Lv. This is possible because there are many reasonably long-lived [[isotopes of curium]] that can be used to make a target.<ref name="Zagrebaev" /> The light isotopes can be made by fusing [[curium-243]] with calcium-48. They would undergo a chain of alpha decays, ending at [[transactinide]] isotopes that are too light to achieve by hot fusion and too heavy to be produced by cold fusion.<ref name="Zagrebaev" /> The same neutron-deficient isotopes are also reachable in reactions with projectiles heavier than <sup>48</sup>Ca, which will be necessary to reach elements beyond atomic number 118 (or possibly [[ununennium|119]]); this is how <sup>288</sup>Lv and <sup>289</sup>Lv were discovered.<ref name=jinr2024>{{Cite web |url=https://indico.jinr.ru/event/4343/contributions/28663/attachments/20748/36083/U%20+%20Cr%20AYSS%202024.pptx |title=Synthesis and study of the decay properties of isotopes of superheavy element Lv in Reactions <sup>238</sup>U + <sup>54</sup>Cr and <sup>242</sup>Pu + <sup>50</sup>Ti |last=Ibadullayev |first=Dastan |date=2024 |website=jinr.ru |publisher=[[Joint Institute for Nuclear Research]] |access-date=2 November 2024 |quote=}}</ref><ref name=Lv288>{{cite news |url=http://www.jinr.ru/posts/v-lyar-oiyai-vpervye-v-mire-sintezirovan-livermorij-288/ |title=В ЛЯР ОИЯИ впервые в мире синтезирован ливерморий-288 |trans-title=Livermorium-288 was synthesized for the first time in the world at FLNR JINR |language=ru |date=23 October 2023 |publisher=Joint Institute for Nuclear Research |access-date=18 November 2023}}</ref>

The synthesis of the heavy isotopes <sup>294</sup>Lv and <sup>295</sup>Lv could be accomplished by fusing the heavy curium isotope [[curium-250]] with calcium-48. The [[cross section (physics)|cross section]] of this nuclear reaction would be about 1&nbsp;[[barn (unit)|picobarn]], though it is not yet possible to produce <sup>250</sup>Cm in the quantities needed for target manufacture.<ref name="Zagrebaev" /> Alternatively, <sup>294</sup>Lv could be produced via charged-particle evaporation in the <sup>251</sup>Cf(<sup>48</sup>Ca,pn) reaction.<ref name=Yerevan2023PPT>{{cite conference |url=https://indico.jinr.ru/event/3622/contributions/20021/attachments/15292/25806/Yerevan2023.pdf |title=Interesting fusion reactions in superheavy region |first1=J. |last1=Hong |first2=G. G. |last2=Adamian |first3=N. V. |last3=Antonenko |first4=P. |last4=Jachimowicz |first5=M. |last5=Kowal |conference=IUPAP Conference "Heaviest nuclei and atoms" |publisher=Joint Institute for Nuclear Research |date=26 April 2023 |access-date=30 July 2023}}</ref><ref name=pxn>{{cite journal |last1=Hong |first1=J. |last2=Adamian |first2=G. G. |last3=Antonenko |first3=N. V. |date=2017 |title=Ways to produce new superheavy isotopes with ''Z''&nbsp;=&nbsp;111–117 in charged particle evaporation channels |journal=Physics Letters B |volume=764 |pages=42–48 |doi=10.1016/j.physletb.2016.11.002 |bibcode=2017PhLB..764...42H|doi-access=free }}</ref> After a few alpha decays, these livermorium isotopes would reach nuclides at the [[line of beta stability]]. Additionally, [[electron capture]] may also become an important decay mode in this region, allowing affected nuclei to reach the middle of the island. For example, it is predicted that <sup>295</sup>Lv would alpha decay to <sup>291</sup>[[flerovium|Fl]], which would undergo successive electron capture to <sup>291</sup>Nh and then <sup>291</sup>[[copernicium|Cn]] which is expected to be in the middle of the island of stability and have a half-life of about 1200&nbsp;years, affording the most likely hope of reaching the middle of the island using current technology. A drawback is that the decay properties of superheavy nuclei this close to the line of beta stability are largely unexplored.<ref name="Zagrebaev" />

Other possibilities to synthesize nuclei on the island of stability include quasifission (partial fusion followed by fission) of a massive nucleus.<ref name="ZG" /> Such nuclei tend to fission, expelling doubly [[magic number (physics)|magic]] or nearly doubly magic fragments such as [[calcium-40]], [[tin-132]], [[lead-208]], or [[bismuth-209]].<ref name="jinr20006">{{cite web|title=JINR Annual Reports 2000–2006|url=http://www1.jinr.ru/Reports/Reports_eng_arh.html|publisher=[[Joint Institute for Nuclear Research|JINR]]|access-date=2013-08-27}}</ref> Recently it has been shown that the multi-nucleon transfer reactions in collisions of actinide nuclei (such as [[uranium]] and [[curium]]) might be used to synthesize the neutron-rich superheavy nuclei located at the island of stability,<ref name="ZG">{{cite journal|last1=Zagrebaev |first1=V.|last2=Greiner |first2=W.|date=2008|title=Synthesis of superheavy nuclei: A search for new production reactions|journal=[[Physical Review C]]|volume=78 |issue=3 |page=034610|arxiv=0807.2537|bibcode=2008PhRvC..78c4610Z|doi=10.1103/PhysRevC.78.034610}}</ref> although formation of the lighter elements [[nobelium]] or [[seaborgium]] is more favored.<ref name="Zagrebaev" /> One last possibility to synthesize isotopes near the island is to use controlled [[nuclear explosion]]s to create a [[neutron flux]] high enough to bypass the gaps of instability at <sup>258–260</sup>[[fermium|Fm]] and at [[mass number]] 275 (atomic numbers [[rutherfordium|104]] to [[hassium|108]]), mimicking the [[r-process]] in which the [[actinide]]s were first produced in nature and the gap of instability around [[radon]] bypassed.<ref name="Zagrebaev" /> Some such isotopes (especially <sup>291</sup>Cn and <sup>293</sup>Cn) may even have been synthesized in nature, but would have decayed away far too quickly (with half-lives of only thousands of years) and be produced in far too small quantities (about 10<sup>−12</sup> the abundance of [[lead]]) to be detectable as [[primordial nuclide]]s today outside [[cosmic ray]]s.<ref name="Zagrebaev" />

=== Physical and atomic ===
In the [[periodic table]], livermorium is a member of group 16, the chalcogens. It appears below [[oxygen]], [[sulfur]], [[selenium]], [[tellurium]], and polonium. Every previous chalcogen has six electrons in its valence shell, forming a [[valence electron]] configuration of ns<sup>2</sup>np<sup>4</sup>. In livermorium's case, the trend should be continued and the valence electron configuration is predicted to be 7s<sup>2</sup>7p<sup>4</sup>;<ref name="Haire" /> therefore, livermorium will have some similarities to its lighter [[congener (chemistry)|congeners]]. Differences are likely to arise; a large contributing effect is the [[spin–orbit interaction|spin–orbit (SO) interaction]]—the mutual interaction between the electrons' motion and [[Spin (physics)|spin]]. It is especially strong for the superheavy elements, because their electrons move much faster than in lighter atoms, at velocities comparable to the [[speed of light]].<ref name="Thayer">{{cite book |last1=Thayer |first1=John S. |title=Relativistic Methods for Chemists |chapter=Relativistic Effects and the Chemistry of the Heavier Main Group Elements |volume=10 |date=2010 |page=83 |doi=10.1007/978-1-4020-9975-5_2|isbn=978-1-4020-9974-8 |series=Challenges and Advances in Computational Chemistry and Physics }}</ref> In relation to livermorium atoms, it lowers the 7s and the 7p electron energy levels (stabilizing the corresponding electrons), but two of the 7p electron energy levels are stabilized more than the other four.<ref name="Faegri">{{cite journal|last1=Faegri |first1=K.|last2=Saue |first2=T.|date=2001|title=Diatomic molecules between very heavy elements of group 13 and group 17: A study of relativistic effects on bonding|journal=[[Journal of Chemical Physics]]|volume=115 |issue=6 |page=2456|bibcode=2001JChPh.115.2456F|doi=10.1063/1.1385366 |doi-access=free}}</ref> The stabilization of the 7s electrons is called the [[inert pair effect]], and the effect "tearing" the 7p subshell into the more stabilized and the less stabilized parts is called subshell splitting. Computation chemists see the split as a change of the second ([[azimuthal quantum number|azimuthal]]) [[quantum number]] ''l'' from 1 to {{frac|1|2}} and {{frac|3|2}} for the more stabilized and less stabilized parts of the 7p subshell, respectively: the 7p<sub>1/2</sub> subshell acts as a second inert pair, though not as inert as the 7s electrons, while the 7p<sub>3/2</sub> subshell can easily participate in chemistry.<ref name="Haire" /><ref name="Thayer" />{{efn|The quantum number corresponds to the letter in the electron orbital name: 0 to s, 1 to p, 2 to d, etc. See [[azimuthal quantum number]] for more information.}} For many theoretical purposes, the valence electron configuration may be represented to reflect the 7p subshell split as 7s{{su|p=2|w=70%}}7p{{su|b=1/2|p=2|w=70%}}7p{{su|b=3/2|p=2|w=70%}}.<ref name="Haire" />

Inert pair effects in livermorium should be even stronger than in polonium and hence the +2 [[oxidation state]] becomes more stable than the +4 state, which would be stabilized only by the most [[electronegative]] [[ligand]]s; this is reflected in the expected [[ionization energy|ionization energies]] of livermorium, where there are large gaps between the second and third ionization energies (corresponding to the breaching of the unreactive 7p<sub>1/2</sub> shell) and fourth and fifth ionization energies.{{Fricke1975|name}} Indeed, the 7s electrons are expected to be so inert that the +6 state will not be attainable.<ref name="Haire" /> The [[melting point|melting]] and [[boiling point]]s of livermorium are expected to continue the trends down the chalcogens; thus livermorium should melt at a higher temperature than polonium, but boil at a lower temperature.<ref name="B&K" /> It should also be [[density|denser]] than polonium (α-Lv: 12.9&nbsp;g/cm<sup>3</sup>; α-Po: 9.2&nbsp;g/cm<sup>3</sup>); like polonium it should also form an α and a β allotrope.{{Fricke1975|name}}<ref>
{{cite web |url=http://cyclotron.tamu.edu/she2015/assets/pdfs/presentations/Eichler_SHE_2015_TAMU.pdf |title=Gas phase chemistry with SHE – Experiments |last=Eichler |first=Robert |date=2015 |website=cyclotron.tamu.edu |publisher=Texas A & M University |access-date=27 April 2017}}</ref> The electron of a [[hydrogen-like atom|hydrogen-like]] livermorium atom (oxidized so that it only has one electron, Lv<sup>115+</sup>) is expected to move so fast that it has a mass 1.86 times that of a stationary electron, due to [[relativistic quantum chemistry|relativistic effects]]. For comparison, the figures for hydrogen-like polonium and tellurium are expected to be 1.26 and 1.080 respectively.<ref name="Thayer" />

=== Chemical ===
Livermorium is projected to be the fourth member of the 7p series of [[chemical element]]s and the heaviest member of group 16 in the periodic table, below polonium. While it is the least theoretically studied of the 7p elements, its chemistry is expected to be quite similar to that of polonium.{{Fricke1975|name}} The group oxidation state of +6 is known for all the chalcogens apart from oxygen which cannot [[Hypervalent molecule|expand its octet]] and is one of the strongest [[redox|oxidizing agents]] among the chemical elements. Oxygen is thus limited to a maximum +2 state, exhibited in the fluoride [[oxygen difluoride|OF<sub>2</sub>]]. The +4 state is known for [[sulfur]], [[selenium]], [[tellurium]], and polonium, undergoing a shift in stability from reducing for sulfur(IV) and selenium(IV) through being the most stable state for tellurium(IV) to being oxidizing in polonium(IV). This suggests a decreasing stability for the higher oxidation states as the group is descended due to the increasing importance of relativistic effects, especially the inert pair effect.<ref name="Thayer" /> The most stable oxidation state of livermorium should thus be +2, with a rather unstable +4 state. The +2 state should be about as easy to form as it is for [[beryllium]] and [[magnesium]], and the +4 state should only be achieved with strongly electronegative ligands, such as in livermorium(IV) fluoride (LvF<sub>4</sub>).<ref name="Haire" /> The +6 state should not exist at all due to the very strong stabilization of the 7s electrons, making the valence core of livermorium only four electrons.{{Fricke1975|name}} The lighter chalcogens are also known to form a −2 state as [[oxide]], [[sulfide]], [[selenide]], [[telluride (chemistry)|telluride]], and [[polonide]]; due to the destabilization of livermorium's 7p<sub>3/2</sub> subshell, the −2 state should be very unstable for livermorium, whose chemistry should be essentially purely cationic,<ref name="Haire" /> though the larger subshell and spinor energy splittings of livermorium as compared to polonium should make Lv<sup>2−</sup> slightly less unstable than expected.<ref name="Thayer" />
 	
Livermorium hydride (LvH<sub>2</sub>) would be the heaviest [[hydrogen chalcogenide|chalcogen hydride]] and the heaviest homolog of [[water]] (the lighter ones are [[hydrogen sulfide|H<sub>2</sub>S]], [[hydrogen selenide|H<sub>2</sub>Se]], [[hydrogen telluride|H<sub>2</sub>Te]], and [[polonium hydride|PoH<sub>2</sub>]]). Polane (polonium hydride) is a more [[covalent]] compound than most metal hydrides because polonium straddles the border between [[metal]] and [[metalloid]] and has some nonmetallic properties: it is intermediate between a [[hydrogen halide]] like [[hydrogen chloride]] (HCl) and a [[metal hydride]] like [[stannane]] ([[tin|Sn]]H<sub>4</sub>). Livermorane should continue this trend: it should be a hydride rather than a livermoride, but still a covalent [[molecule|molecular]] compound.<ref name="Nash">{{cite journal |last1=Nash |first1=Clinton S. |last2=Crockett |first2=Wesley W. |date=2006 |title=An Anomalous Bond Angle in (116)H<sub>2</sub>. Theoretical Evidence for Supervalent Hybridization. |journal=The Journal of Physical Chemistry A |volume=110 |issue=14 |pages=4619–4621 |doi=10.1021/jp060888z |pmid=16599427 |bibcode=2006JPCA..110.4619N |url=https://figshare.com/articles/An_Anomalous_Bond_Angle_in_116_H_sub_2_sub_Theoretical_Evidence_for_Supervalent_Hybridization/3227647 }}</ref> Spin-orbit interactions are expected to make the Lv–H bond longer than expected from [[periodic trends]] alone, and make the H–Lv–H bond angle larger than expected: this is theorized to be because the unoccupied 8s orbitals are relatively low in energy and can [[orbital hybridization|hybridize]] with the valence 7p orbitals of livermorium.<ref name="Nash" /> This phenomenon, dubbed "supervalent hybridization",<ref name="Nash" /> has some analogues in non-relativistic regions in the periodic table; for example, molecular [[calcium difluoride]] has 4s and 3d involvement from the [[calcium]] atom.<ref>{{Greenwood&Earnshaw2nd|page=117}}</ref> The heavier livermorium di[[halide]]s are predicted to be [[linear molecular geometry|linear]], but the lighter ones are predicted to be [[bent molecular geometry|bent]].<ref>{{cite journal | last1 = Van WüLlen | first1 = C. | last2 = Langermann | first2 = N. | doi = 10.1063/1.2711197 | title = Gradients for two-component quasirelativistic methods. Application to dihalogenides of element 116 | journal = The Journal of Chemical Physics | volume = 126 | issue = 11 | page = 114106 | year = 2007 | pmid = 17381195|bibcode = 2007JChPh.126k4106V }}</ref>