Superheavy element

Superheavy elements
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
Z ≥ 104 (Rf)

Superheavy elements, also known as transactinide elements, transactinides, or super-heavy elements, or superheavies for short, are the chemical elements with atomic number greater than 104.[1] The superheavy elements are those beyond the actinides in the periodic table; the last actinide is lawrencium (atomic number 103). By definition, superheavy elements are also transuranium elements, i.e., having atomic numbers greater than that of uranium (92). Depending on the definition of group 3 adopted by authors, lawrencium may also be included to complete the 6d series.[2][3][4][5]

Glenn T. Seaborg first proposed the actinide concept, which led to the acceptance of the actinide series. He also proposed a transactinide series ranging from element 104 to 121 and a superactinide series approximately spanning elements 122 to 153 (though more recent work suggests the end of the superactinide series to occur at element 157 instead). The transactinide seaborgium was named in his honor.[6][7]

Superheavies are radioactive and have only been obtained synthetically in laboratories. No macroscopic sample of any of these elements has ever been produced. Superheavies are all named after physicists and chemists or important locations involved in the synthesis of the elements.

IUPAC defines an element to exist if its lifetime is longer than 10−14 seconds, which is the time it takes for the atom to form an electron cloud.[8]

The known superheavies form part of the 6d and 7p series in the periodic table. Except for rutherfordium and dubnium (and lawrencium if it is included), even the longest-lived known isotopes of superheavies have half-lives of minutes or less. The element naming controversy involved elements 102109. Some of these elements thus used systematic names for many years after their discovery was confirmed. (Usually the systematic names are replaced with permanent names proposed by the discoverers relatively soon after a discovery has been confirmed.)

  1. ^ "Superheavy Element Discovery | Glenn T. Seaborg Institute". seaborg.llnl.gov. Retrieved 2024-09-02.
  2. ^ Neve, Francesco (2022). "Chemistry of superheavy transition metals". Journal of Coordination Chemistry. 75 (17–18): 2287–2307. doi:10.1080/00958972.2022.2084394. S2CID 254097024.
  3. ^ Mingos, Michael (1998). Essential Trends in Inorganic Chemistry. Oxford University Press. p. 387. ISBN 978-0-19-850109-1.
  4. ^ "A New Era of Discovery: the 2023 Long Range Plan for Nuclear Science" (PDF). U.S. Department of Energy. October 2023. Archived from the original (PDF) on 2023-10-05. Retrieved 20 October 2023 – via OSTI. Superheavy elements (Z > 102) are teetering at the limits of mass and charge.
  5. ^ Kragh, Helge (2017). "The search for superheavy elements: Historical and philosophical perspectives". arXiv:1708.04064 [physics.hist-ph].
  6. ^ IUPAC Provisional Recommendations for the Nomenclature of Inorganic Chemistry (2004) (online draft of an updated version of the "Red Book" IR 3-6) Archived October 27, 2006, at the Wayback Machine
  7. ^ Morss, Lester R.; Edelstein, Norman M.; Fuger, Jean, eds. (2006). The Chemistry of the Actinide and Transactinide Elements (3rd ed.). Dordrecht, The Netherlands: Springer. ISBN 978-1-4020-3555-5.
  8. ^ "Kernchemie". www.kernchemie.de.