Periodic table with elements colored according to the half-life of their most stable isotope.
Of the elements with atomic numbers 1 to 92, most can be found in nature, having stableisotopes (such aslead) or very long-livedradioisotopes (such asuranium), or existing as commondecay products of the decay of uranium andthorium (such asradium). The exceptions aretechnetium,promethium,astatine, andfrancium; all four occur in nature, but only in very minor branches of the uranium and thorium decay chains, and thus all except francium were first discovered by synthesis in the laboratory rather than in nature.
All elements with higher atomic numbers have been first discovered in the laboratory, withneptunium andplutonium (the first two of these) later discovered in nature. They are allradioactive, with ahalf-life much shorter than theage of the Earth, so any primordial (i.e. present at the Earth's formation) atoms of these elements, have long since decayed. Trace amounts of neptunium and plutonium form in some uranium-rich rock, and small amounts are produced during atmospheric tests ofnuclear weapons. These two elements are generated byneutron capture inuranium ore with subsequentbeta decays (e.g.238U +n →239U →239Np →239Pu).
All elements beyond plutonium are entirelysynthetic, at least on Earth;[1][2] they are created innuclear reactors orparticle accelerators. The half-lives of these elements show a general trend of decreasing as atomic numbers increase. There are exceptions, however, including several isotopes ofcurium anddubnium. Some heavier elements in this series, around atomic numbers 110–114, are thought to break the trend and demonstrate increased nuclear stability, comprising the theoreticalisland of stability.[3]
Transuranic elements are difficult and expensive to produce, and their prices increase rapidly with atomic number. As of 2008, the cost of weapons-grade plutonium was around $4,000/gram,[4] andcalifornium exceeded $60,000,000/gram.[5]Einsteinium is the heaviest element that has been produced in macroscopic quantities.[6]
Transuranic elements that have not been discovered, or have been discovered but are not yet officially named, useIUPAC'ssystematic element names. The naming of transuranic elements may be a source ofcontroversy.
102.nobelium, No, named afterAlfred Nobel (1958). The element was originally claimed by a team at theNobel Institute in Sweden (1957) – though it later became apparent that the Swedish team had not discovered the element, the LBNL team decided to adopt their namenobelium. This discovery was also claimed by JINR, which doubted the LBNL claim, and named the elementjoliotium (Jl) afterFrédéric Joliot-Curie (1965). IUPAC concluded that the JINR had been the first to convincingly synthesize the element (1965), but retained the namenobelium as deeply entrenched in the literature.
103.lawrencium, Lr, named afterErnest Lawrence, a physicist best known for development of thecyclotron, and the person for whomLawrence Livermore National Laboratory and LBNL (which hosted the creation of these transuranium elements) are named (1961). This discovery was also claimed by the JINR (1965), which doubted the LBNL claim and proposed the namerutherfordium (Rf) afterErnest Rutherford. IUPAC concluded that credit should be shared, retaining the namelawrencium as entrenched in the literature.
104.rutherfordium, Rf, named afterErnest Rutherford, who was responsible for the concept of theatomic nucleus (1969). This discovery was also claimed by JINR, led principally byGeorgy Flyorov: they named the elementkurchatovium (Ku), afterIgor Kurchatov. IUPAC concluded that credit should be shared, and adopted the LBNL namerutherfordium.
105.dubnium, Db, an element that is named afterDubna, where JINR is located. Originally namedhahnium (Ha) in honor ofOtto Hahn by the Berkeley group (1970). This discovery was also claimed by JINR, which named itnielsbohrium (Ns) afterNiels Bohr. IUPAC concluded that credit should be shared, and renamed the elementdubnium to honour the JINR team.
106.seaborgium, Sg, named afterGlenn T. Seaborg. This name caused controversy because Seaborg was still alive, but it eventually became accepted by international chemists (1974). This discovery was also claimed by JINR. IUPAC concluded that the Berkeley team had been the first to convincingly synthesize the element.
107.bohrium, Bh, named after Danish physicistNiels Bohr, important in the elucidation of the structure of theatom (1981). This discovery was also claimed by JINR. IUPAC concluded that the GSI had been the first to convincingly synthesise the element. The GSI team had originally proposednielsbohrium (Ns) to resolve the naming dispute on element 105, but this was changed by IUPAC as there was no precedent for using a scientist's first name in an element name.
108.hassium, Hs, named after theLatin form of the name ofHessen, the GermanBundesland where this work was performed (1984). This discovery was also claimed by JINR. IUPAC concluded that the GSI had been the first to convincingly synthesize the element, while acknowledging the pioneering work at JINR.
110.darmstadtium, Ds, named afterDarmstadt, Germany, the city in which this work was performed (1994). This discovery was also claimed by JINR, which proposed the namebecquerelium afterHenri Becquerel, and by LBNL, which proposed the namehahnium to resolve the dispute on element 105 (despite having protested the reusing of established names for different elements). IUPAC concluded that GSI had been the first to convincingly synthesize the element.
113.nihonium, Nh, named afterJapan (Nihon inJapanese) where the element was discovered (2004). This discovery was also claimed by JINR. IUPAC concluded that RIKEN had been the first to convincingly synthesize the element.
Superheavy elements, (also known assuperheavies, orsuperheavy atoms, commonly abbreviatedSHE) usually refer to the transactinide elements beginning withrutherfordium (atomic number 104). (Lawrencium, the first 6d element, is sometimes but not always included as well.) 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 hours to just milliseconds, which also makes them extremely hard to study.[7][8]
Superheavies 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, in quantities on the atomic scale, and no method of mass creation has been found.[7]
Transuranic elements may be used to synthesize superheavy elements.[9] Elements of the island of stability have potentially important military applications, including the development of compact nuclear weapons.[10] The potential everyday applications are vast;americium is used in devices such assmoke detectors andspectrometers.[11][12]
^Gopka, Vera F.; et al. (December 2004). Zverko, J.; et al. (eds.).On the radioactive shells in peculiar main sequence stars: the phenomenon of Przybylski's star. The A-Star Puzzle, held in Poprad, Slovakia, July 8-13, 2004. IAU Symposium, No. 224. Cambridge, UK: Cambridge University Press. pp. 734–742.Bibcode:2004IAUS..224..734G.doi:10.1017/S174392130500966X.
^Considine, Glenn, ed. (2002).Van Nostrand's Scientific Encyclopedia (9th ed.). New York: Wiley Interscience. p. 738.ISBN978-0-471-33230-5.
^Morel, Andrew (2008). Elert, Glenn (ed.)."Price of Plutonium". The Physics Factbook.Archived from the original on 20 October 2018.
^Silva, Robert J. (2006). "Fermium, Mendelevium, Nobelium and Lawrencium". In Morss, Lester R.; Edelstein, Norman M.; Fuger, Jean (eds.).The Chemistry of the Actinide and Transactinide Elements (Third ed.). Dordrecht, The Netherlands:Springer Science+Business Media.ISBN978-1-4020-3555-5.
Christian Schnier, Joachim Feuerborn, Bong-Jun Lee: Traces of transuranium elements in terrestrial minerals? (Online, PDF-Datei, 493 kB)
Christian Schnier, Joachim Feuerborn, Bong-Jun Lee: The search for super heavy elements (SHE) in terrestrial minerals using XRF with high energy synchrotron radiation. (Online, PDF-Datei, 446 kB)
