Nihonium

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Nihonium, 113Nh
Nihonium
Pronunciation/nɪˈhoʊniəm/ ​(nih-HOH-nee-əm)
Mass number[286]
Nihonium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Tl
↑
Nh
↓
(Uhs)
copernicium ← nihonium → flerovium
Atomic number (Z)113
Groupgroup 13 (boron group)
Periodperiod 7
Block  p-block
Electron configuration[Rn] 5f14 6d10 7s2 7p1 (predicted)[1]
Electrons per shell2, 8, 18, 32, 32, 18, 3 (predicted)
Physical properties
Phase at STPsolid (predicted)[1][2][3]
Melting point700 K ​(430 °C, ​810 °F) (predicted)[1]
Boiling point1430 K ​(1130 °C, ​2070 °F) (predicted)[1][4]
Density (near r.t.)16 g/cm3 (predicted)[4]
Heat of fusion7.61 kJ/mol (extrapolated)[3]
Heat of vaporization130 kJ/mol (predicted)[2][4]
Atomic properties
Oxidation states(−1), (+1), (+3), (+5) (predicted)[1][4][5]
Ionization energies
  • 1st: 704.9 kJ/mol (predicted)[1]
  • 2nd: 2240 kJ/mol (predicted)[4]
  • 3rd: 3020 kJ/mol (predicted)[4]
  • (more)
Atomic radiusempirical: 170 pm (predicted)[1]
Covalent radius172–180 pm (extrapolated)[3]
Other properties
Natural occurrencesynthetic
Crystal structure ​hexagonal close-packed (hcp)
Hexagonal close-packed crystal structure for nihonium

(predicted)[6][7]
CAS Number54084-70-7
History
NamingAfter Japan (Nihon in Japanese)
DiscoveryRiken (Japan, first undisputed claim 2004)
JINR (Russia) and Livermore (US, first announcement 2003)
Isotopes of nihonium
Main isotopes[8] Decay
abun­dance half-life (t1/2) mode pro­duct
278Nh synth 0.002 s α 274Rg
282Nh synth 0.061 s α 278Rg
283Nh synth 0.123 s α 279Rg
284Nh synth 0.90 s α 280Rg
ε 284Cn
285Nh synth 2.1 s α 281Rg
SF –
286Nh synth 9.5 s α 282Rg
287Nh synth 5.5 s?[9] α 283Rg
290Nh synth 2 s?[10] α 286Rg
 Category: Nihonium
| references

Ununtrium (Template:PronEng or /əˈnʌntriəm/) is the temporary name of a synthetic element in the periodic table that has the temporary symbol Uut and has the atomic number 113.

Ununtrium
Common English pronunciation of ununtrium
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It has been synthesised both directly in "cold" and "warm" fusion reactions. It was first observed in the decay of ununpentium. Only eight atoms of ununtrium have been observed to date. Following periodic trends it is expected to be a soft, silvery metal.

Discovery Profile

The first report of ununtrium was in August 2003 when it was identified as a decay product of ununpentium. These results were published on February 1, 2004, by a team composed of Russian scientists at Dubna (Joint Institute for Nuclear Research), and American scientists at the Lawrence Livermore National Laboratory.[11] [12]



On July 23, 2004, a team of Japanese scientists at RIKEN detected a single atom of 278Uut using the cold fusion reaction between Bismuth-209 and zinc-70. They published their results on September 28, 2004.[13]



Support for their claim appeared in 2004 when scientists at the Institute of Modern Physics (IMP) identified 266Bh as decaying with identical properties to their single event (see bohrium).

The RIKEN team produced a further atom on April 2, 2005, although the decay data was different from the first chain, and may be due to the formation of a meta-stable isomer.

The Dubna-Livermore collaboration has strengthened their claim for the discovery of ununtrium by conducting chemical experiments on the decay daughter 268Db. In experiments in Jun 2004 and Dec 2005, the Dubnium isotope was successfully identified by milking the Db fraction and measuring any SF activities. Both the half-life and decay mode were confirmed for the proposed 268Db which lends support to the assignment of Z=115 and Z=113 to the parent and daughter nuclei.[14] [15]

Theoretical estimates of alpha-decay half-lives of alpha-decay chains from element 113 are in good agreement with the experimental data.[16]

Naming

Current names

The element with Z=113 is historically known as eka-thallium. Ununtrium (Uut) is a temporary IUPAC systematic element name. Research scientists usually refer to the element simply as element 113 (E113).

Proposed names by claimants

Claims to the discovery of element 113 have been put forward by Dmitriev of the Dubna team and Morita of the RIKEN team. The JWP will decide to whom the right to suggest a name will be given. The IUPAC have the final say on the official adoption of a name. The table below gives the names that the teams above have suggested and which can be verified by press interviews.

Group Proposed Name Proposed Symbol Derivation
RIKEN Japonium[17] Jp Japan - country of group claimants
RIKEN Rikenium[17] Rk RIKEN - institute of group claimants

Disallowed names

According to IUPAC rules, names used for previous elements that have ultimately not been adopted are not allowed to be proposed for future use. The table below summarises those names which are probably not allowed to be proposed by the claimant laboratories under the rules.

Group Claim Affected Disallowed Name Disallowed Symbol Reason
RIKEN Nipponium Np (Np is already used for Neptunium) Used for claimed discovery of element 43
Dubna Russium Rs Used for claimed discovery of element 43

Plausible names

Many speculative names appear in popular literature. The table below lists these names in the case where they obey IUPAC rules and are plausible with regard to the claimant laboratories. Rumoured suggestions (*) linked to the claimant laboratories are also included.

Group Link Suggested Name Suggested Synbol Derivation Comments
RIKEN Nihonium * Nh Nihon - Japanese for Japan more appropriate, a really local name
Dubna Becquerelium * Bq Henri Becquerel - discoverer of radioactivity Dubna team suggested the name for element 110[18]

Electronic structure


Ununtrium is element 113 in the Periodic Table. The two forms of the projected electronic structure are:

Bohr model: 2, 8, 18, 32, 32, 18, 3

Quantum mechanical model: 1s22s22p63s23p64s23d10 4p65s24d105p66s24f145d10 6p67s25f146d107p1




Extrapolated chemical properties of eka-thallium

Oxidation states

Element 113 is projected to be the first member of the 7p series of non-metals and the heaviest member of group 13 (IIIA) in the Periodic Table, below thallium. Each of the members of this group show the group oxidation state of +III. However, thallium has a tendency to form only a stable +I state due to the "inert pair effect", explained by the relativistic stabilisation of the 7s-orbitals, resulting in a higher ionisation potential and weaker tendency to participate in bonding.

Chemistry

Element 113 should portray eka-thallium chemical properties and should therefore from a monoxide, Uut2O, and monohalides, UutF, UutCl, UUtBr and UutI. If the +III state is accessible, it is likely that it is only possible in the oxide, Uut2O3, and fluoride, UutF3.

History of synthesis of isotopes by cold fusion

209Bi(70Zn,xn)279-x113 (x=1)

The synthesis of element 113 was first attempted in 1998 by the team at GSI using the above cold fusion reaction. In two separate runs, they were unable to detect any atoms and calculated a cross section limit of 900 fb.[19] They repeated the experiment in 2003 and lowered the limit further to 400 fb.[19] In late 2003, the emerging team at RIKEN using their efficient apparatus GARIS attempted the reaction and reached a limit of 140 fb. In December 2003-August 2004, they resulted to 'brute force' and performed an eight-month-long irradiation in which they increased the sensitivity to 51 fb. They were able to detect a single atom of 278113.[13] They repeated the reaction in several runs in 2005 and were able to synthesise a second atom. They calculated a record-low 31 fb for the cross section for the 2 atoms.

History of synthesis of isotopes by hot fusion

237Np(48Ca,xn)285-x113 (x=3)

In June 2006, the Dubna-Livermore team synthesised ununtrium directly in the "warm" fusion reaction between neptunium-237 and calcium-48 nuclei. Two atoms of 282Uut were detected with a cross section of 900 fb. [20]

Chronology of isotope discovery

Isotope Year discovered discovery reaction
278Uut 2004 209Bi(70Zn,n) [13]
279Uut unknown
280Uut unknown
281Uut unknown
282Uut 2006 237Np(48Ca,3n)[20]
283Uut 2003 243Am(48Ca,4n)[11]
284Uut 2003 243Am(48Ca,3n)[11]

Yields of isotopes

Cold fusion

The table below provides cross-sections and excitation energies for cold fusion reactions producing ununtrium isotopes directly. Data in bold represents maxima derived from excitation function measurements. + represents an observed exit channel.

Projectile Target CN 1n 2n 3n
70Zn 209Bi 279Uut 31 fb

Hot Fusion

The table below provides cross-sections and excitation energies for hot fusion reactions producing ununtrium isotopes directly. Data in bold represents maxima derived from excitation function measurements. + represents an observed exit channel.

Projectile Target CN 3n 4n 5n
48Ca 237Np 285Uut 0.9pb , 39.1 MeV [20]

References

  1. ^ a b c d e f g Hoffman, Darleane C.; Lee, Diana M.; Pershina, Valeria (2006). "Transactinides and the future elements". In Morss; Edelstein, Norman M.; Fuger, Jean (eds.). The Chemistry of the Actinide and Transactinide Elements (3rd ed.). Dordrecht, The Netherlands: Springer Science+Business Media. ISBN 978-1-4020-3555-5.
  2. ^ a b Seaborg, Glenn T. (c. 2006). "transuranium element (chemical element)". Encyclopædia Britannica. Retrieved 2010-03-16.
  3. ^ a b c Bonchev, Danail; Kamenska, Verginia (1981). "Predicting the Properties of the 113–120 Transactinide Elements". Journal of Physical Chemistry. 85 (9): 1177–1186. doi:10.1021/j150609a021.
  4. ^ a b c d e f Fricke, Burkhard (1975). "Superheavy elements: a prediction of their chemical and physical properties". Recent Impact of Physics on Inorganic Chemistry. Structure and Bonding. 21: 89–144. doi:10.1007/BFb0116498. ISBN 978-3-540-07109-9. Retrieved 4 October 2013.
  5. ^ Thayer, John S. (2010). "Relativistic Effects and the Chemistry of the Heavier Main Group Elements". In Barysz, Maria; Ishikawa, Yasuyuki (eds.). Relativistic Methods for Chemists. Challenges and Advances in Computational Chemistry and Physics. Vol. 10. Springer. pp. 63–67. doi:10.1007/978-1-4020-9975-5_2. ISBN 978-1-4020-9974-8.
  6. ^ Keller, O. L. Jr.; Burnett, J. L.; Carlson, T. A.; Nestor, C. W. Jr. (1969). "Predicted Properties of the Super Heavy Elements. I. Elements 113 and 114, Eka-Thallium and Eka-Lead". The Journal of Physical Chemistry. 74 (5): 1127−1134. doi:10.1021/j100700a029.
  7. ^ Atarah, Samuel A.; Egblewogbe, Martin N. H.; Hagoss, Gebreyesus G. (2020). "First principle study of the structural and electronic properties of Nihonium". MRS Advances: 1–9. doi:10.1557/adv.2020.159.
  8. ^ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  9. ^ Hofmann, S.; Heinz, S.; Mann, R.; Maurer, J.; Münzenberg, G.; Antalic, S.; Barth, W.; et al. (2016). "Remarks on the Fission Barriers of SHN and Search for Element 120". In Peninozhkevich, Yu. E.; Sobolev, Yu. G. (eds.). Exotic Nuclei: EXON-2016 Proceedings of the International Symposium on Exotic Nuclei. Exotic Nuclei. pp. 155–164. ISBN 9789813226555.
  10. ^ Hofmann, S.; Heinz, S.; Mann, R.; Maurer, J.; Münzenberg, G.; Antalic, S.; Barth, W.; et al. (2016). "Review of even element super-heavy nuclei and search for element 120". The European Physics Journal A. 2016 (52). doi:10.1140/epja/i2016-16180-4.
  11. ^ a b c "Experiments on the synthesis of element 115 in the reaction 243Am(48Ca,xn)291-x115", Oganessian et al., JINR Preprints, 2003. Retrieved on 2008-03-03
  12. ^ "Experiments on the synthesis of element 115 in the reaction 243Am(48Ca,xn)291-x115", Oganessian et al., Phys. Rev. C 69, 021601 (2004). Retrieved on 2008-03-03
  13. ^ a b c "Experiment on the Synthesis of Element 113 in the Reaction 209Bi(70Zn, n)278113", Morita et al., J. Phys. Joc. Jpn., 2004, 73, 10. Retrieved on 2008-03-03
  14. ^ "RESULTS OF THE EXPERIMENT ON CHEMICAL IDENTIFICATION OF Db AS A DECAY PRODUCT OF ELEMENT 115", Oganessian et al., JINR preprints, 2004. Retrieved on 2008-03-03
  15. ^ "Synthesis of elements 115 and 113 in the reaction 243Am + 48Ca", Oganessian et al., Phys. Rev. C72, 034611 (2005). Retrieved on 2008-03-03
  16. ^ P. Roy Chowdhury, D. N. Basu and C. Samanta (2007). "α decay chains from element 113". Phys. Rev. C. 75: 047306. doi:10.1103/PhysRevC.75.047306.
  17. ^ a b "RIKEN NEWS November 2004". Retrieved 2008-02-09.
  18. ^ Chemistry : Periodic Table : darmstadtium : historical information
  19. ^ a b "Search for element 113", Hofmann et al., GSI report 2003. Retrieved on 2008-03-03
  20. ^ a b c "Synthesis of the isotope 282113 in the 237Np+48Ca fusion reaction", Oganessian et al., Phys. Rev. C76, 011601(R) (2007). Retrieved on 2008-03-03

See also


External links

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