Editing Unbinilium (section)

===Chemical===
{| class="wikitable floatright" style="font-size:85%;"
|+ Bond lengths and bond-dissociation energies of alkaline earth metal dimers. Data for Ba<sub>2</sub>, Ra<sub>2</sub> and Ubn<sub>2</sub> is predicted.<ref name="Pershina" />
! Compound
! Bond length<br />(Å)
! Bond-dissociation<br />energy (eV)
|-
! Ca<sub>2</sub>
| 4.277
| 0.14
|-
! Sr<sub>2</sub>
| 4.498
| 0.13
|-
! Ba<sub>2</sub>
| 4.831
| 0.23
|-
! Ra<sub>2</sub>
| 5.19
| 0.11
|-
! Ubn<sub>2</sub>
| 5.65
| 0.02
|}
The chemistry of unbinilium is predicted to be similar to that of the alkaline earth metals,<ref name="Haire" /> but it would probably behave more like calcium or strontium<ref name="Haire" /> than barium or radium. Like strontium, unbinilium should react vigorously with air to form an oxide (UbnO) and with water to form the hydroxide (Ubn(OH)<sub>2</sub>), which would be a strong [[base (chemistry)|base]], and releasing [[hydrogen]] gas. It should also react with the [[halogen]]s to form salts such as UbnCl<sub>2</sub>.<ref name="emsley">{{cite book|last=Emsley|first=John|title=Nature's Building Blocks: An A-Z Guide to the Elements|edition=New|date=2011|publisher=Oxford University Press|location=New York, NY|isbn=978-0-19-960563-7|page=586}}</ref> While these reactions would be expected from [[periodic trends]], their lowered intensity is somewhat unusual, as ignoring relativistic effects, periodic trends would predict unbinilium to be even more reactive than barium or radium. This lowered [[reactivity (chemistry)|reactivity]] is due to the relativistic stabilization of unbinilium's valence electron, increasing unbinilium's first ionization energy and decreasing the [[metallic radius|metallic]] and [[ionic radius|ionic radii]];<ref name="EB">{{cite encyclopedia|author=Seaborg|url=http://www.britannica.com/EBchecked/topic/603220/transuranium-element|title=transuranium element (chemical element)|encyclopedia=Encyclopædia Britannica|date=c. 2006|access-date=2010-03-16}}</ref> this effect is already seen for radium.<ref name="Haire" /> On the other hand, the ionic radius of the Ubn<sup>2+</sup> ion is predicted to be larger than that of Sr<sup>2+</sup>, because the 7p orbitals are destabilized and are thus larger than the p-orbitals of the lower shells.<ref name=Thayer/>

Unbinilium may also show the +4 [[oxidation state]],<ref name="Haire" /> which is not seen in any other alkaline earth metal,<ref name="Greenwood&Earnshaw">{{Greenwood&Earnshaw|p=28}}</ref> in addition to the +2 oxidation state that is characteristic of the other alkaline earth metals and is also the main oxidation state of all the known alkaline earth metals: this is because of the destabilization and expansion of the 7p<sub>3/2</sub> spinor, causing its outermost electrons to have a lower ionization energy than what would otherwise be expected.<ref name="Haire" /><ref name="Greenwood&Earnshaw" /> The +6 state involving all the 7p<sub>3/2</sub> electrons has been suggested in a [[hexafluoride]], UbnF<sub>6</sub>.<ref name=Cao/> The +1 state may also be isolable.<ref name="Thayer" /> Many unbinilium compounds are expected to have a large [[covalent]] character, due to the involvement of the 7p<sub>3/2</sub> electrons in the bonding: this effect is also seen to a lesser extent in radium, which shows some 6s and 6p<sub>3/2</sub> contribution to the bonding in [[radium fluoride]] (RaF<sub>2</sub>) and astatide (RaAt<sub>2</sub>), resulting in these compounds having more covalent character.<ref name="Thayer" /> The [[standard reduction potential]] of the Ubn<sup>2+</sup>/Ubn couple is predicted to be −2.9&nbsp;V, which is almost exactly the same as that for the Sr<sup>2+</sup>/Sr couple of strontium (&minus;2.899&nbsp;V).<ref name="BFricke" />

{| class="wikitable floatright" style="font-size:85%;"
|+ Bond lengths and bond-dissociation energies of MAu (M = an alkaline earth metal). All data is predicted, except for CaAu.<ref name="Pershina" />
! Compound
! Bond length<br />(Å)
! Bond-dissociation<br />energy (kJ/mol)
|-
! CaAu
| 2.67
| 2.55
|-
! SrAu
| 2.808
| 2.63
|-
! BaAu
| 2.869
| 3.01
|-
! RaAu
| 2.995
| 2.56
|-
! UbnAu
| 3.050
| 1.90
|}
In the gas phase, the alkaline earth metals do not usually form covalently bonded diatomic molecules like the alkali metals do, since such molecules would have the same number of electrons in the bonding and antibonding orbitals and would have very low [[dissociation energy|dissociation energies]].<ref name="Be2">{{cite book |last1=Keeler |first1=James |last2=Wothers |first2=Peter |date=2003 |title=Why Chemical Reactions Happen |publisher=[[Oxford University Press]] |page=74 |isbn=978-0-19-924973-2}}</ref> Thus, the M–M bonding in these molecules is predominantly through [[van der Waals force]]s.<ref name="Pershina" /> The metal–metal [[bond length]]s in these M<sub>2</sub> molecules increase down the group from Ca<sub>2</sub> to Ubn<sub>2</sub>. On the other hand, their metal–metal [[bond-dissociation energy|bond-dissociation energies]] generally increase from Ca<sub>2</sub> to Ba<sub>2</sub> and then drop to Ubn<sub>2</sub>, which should be the most weakly bound of all the group 2 homodiatomic molecules. The cause of this trend is the increasing participation of the p<sub>3/2</sub> and d electrons as well as the relativistically contracted s orbital.<ref name="Pershina" /> From these M<sub>2</sub> dissociation energies, the [[enthalpy of sublimation]] (Δ''H''<sub>sub</sub>) of unbinilium is predicted to be 150&nbsp;kJ/mol.<ref name="Pershina" />

{| class="wikitable floatright" style="font-size:85%;"
|+Bond lengths, harmonic frequency, vibrational anharmonicity and bond-dissociation energies of MH and MAu (M = an alkaline earth metal). Data for UbnH and UbnAu are predicted.<ref name=":0">{{Cite journal|last1=Skripnikov|first1=L.V.|last2=Mosyagin|first2=N.S.|last3=Titov|first3=A.V.|date=January 2013|title=Relativistic coupled-cluster calculations of spectroscopic and chemical properties for element 120|journal=Chemical Physics Letters|volume=555|pages=79–83|doi=10.1016/j.cplett.2012.11.013|arxiv=1202.3527|bibcode=2013CPL...555...79S |s2cid=96581438}}</ref> Data for BaH is taken from experiment,<ref>{{Cite journal|last1=Knight|first1=L. B.|last2=Easley|first2=W. C.|last3=Weltner|first3=W.|last4=Wilson|first4=M.|date=January 1971|title=Hyperfine Interaction and Chemical Bonding in MgF, CaF, SrF, and BaF molecules|journal=The Journal of Chemical Physics|volume=54|issue=1|pages=322–329|doi=10.1063/1.1674610|bibcode=1971JChPh..54..322K |issn=0021-9606}}</ref> except bond-dissociation energy.<ref name=":0" /> Data for BaAu is taken from experiment,<ref>{{Cite book|title=Constants of Diatomic Molecules|publisher=Van Nostrand-Reinhold|year=1979|location=New York}}</ref> except bond-dissociation energy and bond length.<ref name=":0" />
!Compound
!Bond length<br />(Å)
!Harmonic<br />frequency,<br />cm<sup>−1</sup>
!Vibrational<br />anharmonicity,<br />cm<sup>−1</sup>
!Bond-dissociation<br />energy (eV)
|-
|'''UbnH'''
|2.38
|1070
|20.1
|1.00
|-
|'''BaH'''
|2.23
|1168
|14.5
|2.06
|-
|
|
|
|
|
|-
|'''UbnAu'''
|3.03
| 100
| 0.13
|1.80
|-
|'''BaAu'''
|2.91 
| 129
| 0.18
|2.84
|}
The Ubn–[[gold|Au]] bond should be the weakest of all bonds between gold and an alkaline earth metal, but should still be stable. This gives extrapolated medium-sized adsorption enthalpies (−Δ''H''<sub>ads</sub>) of 172&nbsp;kJ/mol on gold (the radium value should be 237&nbsp;kJ/mol) and 50&nbsp;kJ/mol on [[silver]], the smallest of all the alkaline earth metals, that demonstrate that it would be feasible to study the [[chromatography|chromatographic]] [[adsorption]] of unbinilium onto surfaces made of [[noble metal]]s.<ref name="Pershina" /> The Δ''H''<sub>sub</sub> and −Δ''H''<sub>ads</sub> values are correlated for the alkaline earth metals.<ref name="Pershina" />