Unsepttrium
Unsepttrium (/ˌuːnsɛptriəm/), also known as dvi-francium , eka-Ununennium, or element 173, is a possible chemical element which has not been observed to occur naturally, nor has it yet been made. 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] however, if possible, it is likely the heaviest possible neutral element. Its atomic number is 173 and its atomic symbol is Ust.
Unsepttrium in the periodic table | ||||||
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Electrons per shell | 2, 8, 18, 32, 50, 33, 18, 8, 4 (predicted) | |||||
Atomic properties | ||||||
Oxidation states | Template:Infobox element/symbol-to-oxidation-state: Symbol "Ust" not known | |||||
Isotopes of unsepttrium | ||||||
Template:infobox unsepttrium isotopes does not exist | ||||||
The name unsepttrium is a temporary IUPAC systematic element name.
Significance
Although Richard Feynman noted[2] 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, a more thorough analysis calculates the limit to be Z ≈ 173, meaning that neutral atoms most likely cannot exist with atomic number greater than 173.[3] This makes unsepttrium theoretically the heaviest neutral element possible.
Related pages
References
- Seaborg, G. T. (c. 2006). "transuranium element (chemical element)". Encyclopædia Britannica. Retrieved 2010-03-16.
- Elert, G. "Atomic Models". The Physics Hypertextbook. Retrieved 2009-10-09.
- See Extended periodic table and untriseptium.