Transuranium element

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Transuranium elements
in the periodic table
Hydrogen (diatomic nonmetal)
Helium (noble gas)
Lithium (alkali metal)
Beryllium (alkaline earth metal)
Boron (metalloid)
Carbon (polyatomic nonmetal)
Nitrogen (diatomic nonmetal)
Oxygen (diatomic nonmetal)
Fluorine (diatomic nonmetal)
Neon (noble gas)
Sodium (alkali metal)
Magnesium (alkaline earth metal)
Aluminium (post-transition metal)
Silicon (metalloid)
Phosphorus (polyatomic nonmetal)
Sulfur (polyatomic nonmetal)
Chlorine (diatomic nonmetal)
Argon (noble gas)
Potassium (alkali metal)
Calcium (alkaline earth metal)
Scandium (transition metal)
Titanium (transition metal)
Vanadium (transition metal)
Chromium (transition metal)
Manganese (transition metal)
Iron (transition metal)
Cobalt (transition metal)
Nickel (transition metal)
Copper (transition metal)
Zinc (transition metal)
Gallium (post-transition metal)
Germanium (metalloid)
Arsenic (metalloid)
Selenium (polyatomic nonmetal)
Bromine (diatomic nonmetal)
Krypton (noble gas)
Rubidium (alkali metal)
Strontium (alkaline earth metal)
Yttrium (transition metal)
Zirconium (transition metal)
Niobium (transition metal)
Molybdenum (transition metal)
Technetium (transition metal)
Ruthenium (transition metal)
Rhodium (transition metal)
Palladium (transition metal)
Silver (transition metal)
Cadmium (transition metal)
Indium (post-transition metal)
Tin (post-transition metal)
Antimony (metalloid)
Tellurium (metalloid)
Iodine (diatomic nonmetal)
Xenon (noble gas)
Caesium (alkali metal)
Barium (alkaline earth metal)
Lanthanum (lanthanide)
Cerium (lanthanide)
Praseodymium (lanthanide)
Neodymium (lanthanide)
Promethium (lanthanide)
Samarium (lanthanide)
Europium (lanthanide)
Gadolinium (lanthanide)
Terbium (lanthanide)
Dysprosium (lanthanide)
Holmium (lanthanide)
Erbium (lanthanide)
Thulium (lanthanide)
Ytterbium (lanthanide)
Lutetium (lanthanide)
Hafnium (transition metal)
Tantalum (transition metal)
Tungsten (transition metal)
Rhenium (transition metal)
Osmium (transition metal)
Iridium (transition metal)
Platinum (transition metal)
Gold (transition metal)
Mercury (transition metal)
Thallium (post-transition metal)
Lead (post-transition metal)
Bismuth (post-transition metal)
Polonium (post-transition metal)
Astatine (metalloid)
Radon (noble gas)
Francium (alkali metal)
Radium (alkaline earth metal)
Actinium (actinide)
Thorium (actinide)
Protactinium (actinide)
Uranium (actinide)
Neptunium (actinide)
Plutonium (actinide)
Americium (actinide)
Curium (actinide)
Berkelium (actinide)
Californium (actinide)
Einsteinium (actinide)
Fermium (actinide)
Mendelevium (actinide)
Nobelium (actinide)
Lawrencium (actinide)
Rutherfordium (transition metal)
Dubnium (transition metal)
Seaborgium (transition metal)
Bohrium (transition metal)
Hassium (transition metal)
Meitnerium (unknown chemical properties)
Darmstadtium (unknown chemical properties)
Roentgenium (unknown chemical properties)
Copernicium (transition metal)
Ununtrium (unknown chemical properties)
Flerovium (post-transition metal)
Ununpentium (unknown chemical properties)
Livermorium (unknown chemical properties)
Ununseptium (unknown chemical properties)
Ununoctium (unknown chemical properties)
Z > 92

The transuranium elements (also known as transuranic elements) are the chemical elements with atomic numbers greater than 92 (the atomic number of uranium). All of these elements are unstable and decay radioactively into other elements.


Periodic table with elements colored according to the half-life of their most stable isotope.
  Elements which contain at least one stable isotope.
  Slightly radioactive elements: the most stable isotope is very long-lived, with a half-life of over four million years.
  Significantly radioactive elements: the most stable isotope has half-life between 800 and 34,000 years.
  Radioactive elements: the most stable isotope has half-life between one day and 103 years.
  Highly radioactive elements: the most stable isotope has half-life between several minutes and one day.
  Extremely radioactive elements: the most stable isotope has half-life less than several minutes.

Of the elements with atomic numbers 1 to 92, most can be found in nature, having stable (such as hydrogen), or very long half-life (such as uranium) isotopes, or are created as common products of the decay of uranium and thorium (such as radon). The exceptions are elements 43, 61, 85, and 87; all four occur in nature, but only in very minor branches of the uranium and thorium decay chains, and thus all save element 87 were first discovered by synthesis in the laboratory rather than in nature (and even element 87 was discovered from purified samples of its parent, not directly from nature).

All of the elements with higher atomic numbers have been first discovered in the laboratory, with neptunium and plutonium later also discovered in nature. They are all radioactive, with a half-life much shorter than the age of the Earth, so any atoms of these elements, if they ever were present at the Earth's formation, have long since decayed. Trace amounts of neptunium and plutonium form in some uranium-rich rock, and small amounts are produced during atmospheric tests of atomic weapons. These two elements are generated from neutron capture in uranium ore with subsequent beta decays (e.g. 238U + n239U239Np239Pu).

Transuranic elements can be artificially generated synthetic elements, via nuclear reactors or particle accelerators. The half lives of these elements show a general trend of decreasing as atomic numbers increase. There are exceptions, however, including several isotopes of curium and dubnium. Further anomalous elements in this series have been predicted by Glenn T. Seaborg, and are categorised as the “island of stability.”[1]

Heavy transuranic elements are difficult and expensive to produce, and their prices increase rapidly with atomic number. As of 2008, weapons-grade plutonium cost around $4,000/gram,[2] and californium cost $60,000,000/gram.[3] Einsteinium is the heaviest transuranic element that has ever been produced in macroscopic quantities.[4]

Transuranic elements that have not been discovered, or have been discovered but are not yet officially named, use IUPAC's systematic element names. The naming of transuranic elements may be a source of controversy.

Discovery and naming of transuranium elements[edit]

So far, essentially all the transuranium elements have been discovered at four laboratories: Lawrence Berkeley National Laboratory in the United States (elements 93–101, 106, and joint credit for 102–105), the Joint Institute for Nuclear Research in Russia (elements 114–118, and joint credit for 102–105), the GSI Helmholtz Centre for Heavy Ion Research in Germany (elements 107–112), and RIKEN in Japan (element 113).

List of the transuranic elements by chemical series[edit]

The names and symbols of elements 113, 115, 117, and 118 are provisional until their proposed permanent names – respectively, nihonium (Nh), moscovium (Mc), tennessine (Ts), and oganesson (Og) – are accepted by IUPAC after the five-month period of public review.

Super-heavy elements[edit]

Position of the transactinide elements in the periodic table.

Super-heavy elements, (also known as super heavy atoms, commonly abbreviated SHE) usually refer to the transactinide elements beginning with rutherfordium (atomic number 104). They have only been made artificially, and currently serve no practical purpose because their short half-lives cause them to decay after a very short time, ranging from a few minutes to just a few milliseconds (except for dubnium, which has a half life of over a day), which also makes them extremely hard to study.[5][6]

Super-heavy atoms have all been created since the latter half of the 20th century, and are continually being created during the 21st century as technology advances. They are created through the bombardment of elements in a particle accelerator. For example, the nuclear fusion of californium-249 and carbon-12 creates rutherfordium-261. These elements are created in quantities on the atomic scale and no method of mass creation has been found.[5]


Transuranium elements may be utilized to synthesize other super-heavy elements.[7] Elements of the island of stability have potential important military applications, including the development of compact nuclear weapons.[8] The potential every-day applications are vast; the element Americium is utilized in devices like smoke detectors and spectrometers.[9][10]

See also[edit]


  1. ^ Considine, Glenn, ed. (2002). Van Nostrand's Scientific Encyclopedia (9th ed.). New York: Wiley Interscience. p. 738. ISBN 0-471-33230-5. 
  2. ^ "Price of Plutonium". The Physics Factbook. 
  3. ^ Rodger C. Martin and Steven E. Kos. "Applications and Availability of Californium-252 Neutron Sources for Waste Characterization" (pdf). 
  4. ^ Silva, Robert J. (2006). "Fermium, Mendelevium, Nobelium and Lawrencium". In Morss; Edelstein, Norman M.; Fuger, Jean. The Chemistry of the Actinide and Transactinide Elements (3rd ed.). Dordrecht, The Netherlands: Springer Science+Business Media. ISBN 1-4020-3555-1. 
  5. ^ a b Heenen, P. H.; Nazarewicz, W. (2002). "Quest for superheavy nuclei". Europhysics News. 33: 5. Bibcode:2002ENews..33....5H. doi:10.1051/epn:2002102. 
  6. ^ Greenwood, N. N. (1997). "Recent developments concerning the discovery of elements 100–111". Pure and Applied Chemistry. 69: 179. doi:10.1351/pac199769010179. 
  7. ^ Lougheed, R. W.; Landrum, J. H.; Hulet, E. K.; Wild, J. F.; Dougan, R. J.; Dougan, A. D.; Gäggeler, H.; Schädel, M.; Moody, K. J.; Gregorich, K. E. & Seaborg, G. T. (1985). "Search for superheavy elements using 48Ca + 254Esg reaction". Physical Review C. 32 (5): 1760–1763. Bibcode:1985PhRvC..32.1760L. doi:10.1103/PhysRevC.32.1760. 
  8. ^ pp. 129–133, The physical principles of thermonuclear explosives, inertial confinement fusion, and the quest for fourth generation nuclear weapons (Andre Gsponer and Jean-Pierre Hurni 2009)
  9. ^ "Smoke Detectors and Americium", Nuclear Issues Briefing Paper, 35, May 2002, archived from the original on 11 September 2002, retrieved 2015-08-26 
  10. ^ Nuclear Data Viewer 2.4, NNDC

Further reading[edit]