Untriseptium
Untriseptium (/ˌuːntraɪˈsɛptiəm/), also called eka-dubnium[source?] or element 137, is a possible chemical element which has not been synthesized. Due to instabilities, it is not known if this element is possible, as the instabilities may hint that the periodic table ends soon after the island of stability at unbihexium.[1][2] Its atomic number is 137 and symbol is Uts.
General properties | |||||||||||
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Alternative name | feynmanium | ||||||||||
Untriseptium in the periodic table | |||||||||||
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Atomic number (Z) | 137 | ||||||||||
Group | group n/a | ||||||||||
Period | period 8 | ||||||||||
Block | g-block-block | ||||||||||
Electrons per shell | 2, 8, 18, 32, 43, 21, 9, 4 | ||||||||||
Physical properties | |||||||||||
unknown | |||||||||||
Phase at STP | Uts: | ||||||||||
Atomic properties | |||||||||||
Oxidation states | Template:Infobox element/symbol-to-oxidation-state: Symbol "Uts" not known | ||||||||||
Other properties | |||||||||||
Natural occurrence | Uts: | ||||||||||
Main isotopes of untriseptium | |||||||||||
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The name untriseptium is a temporary name.
Importance
It is sometimes called feynmanium (symbol Fy) because Richard Feynman noted[3] that a simplistic interpretation of the relativistic Dirac equation runs into problems with electron orbitals at Z > 1/α = 137, suggesting that neutral atoms cannot exist beyond untriseptium, and that a periodic table of elements based on electron orbitals breaks down at this point. However, a more thorough analysis calculates the limit to be around element 173.[4]
Untriseptium Media
Energy eigenvalues (in eV) for the outermost electrons of elements with Z = 100 through 172, predicted using Dirac–Fock calculations. The − and + signs refer to orbitals with decreased or increased azimuthal quantum number from spin–orbit splitting respectively: p− is p1/2, p+ is p3/2, d− is d3/2, d+ is d5/2, f− is f5/2, f+ is f7/2, g− is g7/2, and g+ is g9/2.
Energy eigenvalues for the 1s, 2s, 2p1/2 and 2p3/2 shells from solutions of the Dirac equation (taking into account the finite size of the nucleus) for Z = 135–175 (–·–), for the Thomas-Fermi potential (—) and for Z = 160–170 with the self-consistent potential (---).
Related pages
References
- ↑ Seaborg, G. T. (c. 2006). "transuranium element (chemical element)". Encyclopædia Britannica. Retrieved 2010-03-16.
- ↑ Cwiok, S.; Heenen, P.-H.; Nazarewicz, W. (2005). "Shape coexistence and triaxiality in the superheavy nuclei". Nature. 433 (7027): 705–9. Bibcode:2005Natur.433..705C. doi:10.1038/nature03336. PMID 15716943. S2CID 4368001.
- ↑ Elert, G. "Atomic Models". The Physics Hypertextbook. Retrieved 2009-10-09.
- ↑ Walter Greiner and Stefan Schramm (2008). "Resource Letter QEDV-1: The QED vacuum". American Journal of Physics. 76 (6): 509. Bibcode:2008AmJPh..76..509G. doi:10.1119/1.2820395., and references therein.