|
Name: Unuhexium |
Boiling Point: unknown Melting Point: unknown Electrons Energy Level: unknown Isotopes: 5 + None Stable Heat of Vaporization: unknown Heat of Fusion: unknown Density: unknown Specific Heat: unknown Atomic Radius: unknown Ionic Radius: unknown Electronegativity: unknown |
| Ununhexium is the temporary
IUPAC systematic name of a synthetic superheavy element in the periodic table that has the
temporary symbol Uuh and has the atomic number 116. Some research has referred to it as
"Eka-Polonium". In 1999, researchers at Lawrence Berkeley National Laboratory announced the discovery of elements 116 and 118 (Ununhexium and Ununoctium), in a paper published in Physical Review Letters. The following year, they published a retraction after other researchers were unable to duplicate the results. In June 2002, the director of the lab announced that the original claim of the discovery of these two elements had been based on data fabricated by the principal author Victor Ninov. Results published on the 6th December 2000 concerning experiments at Dubna in Russia (involving workers from The Joint Institute for Nuclear Research, Dubna, Russian Federation; U.S. Department of Energy's Lawrence Livermore National Laboratory, California, USA; The Research Institute of Atomic Reactors, Dimitrovgrad, Russian Federation; and The State Enterprise Electrohimpribor, Lesnoy, Russian Federation) describe the decay of the isotope 292Uuh. They produced Ununhexium by bombarding atoms of Curium-248 with ions of Calcium-48. This produced Ununhexium-292, an isotope with a half-life of about 0.6 milliseconds (0.0006 seconds), and four free neutrons. |
8 O 15.99 |
| 16 S 32.06 |
|
| 34 Se 78.96 |
|
| 52 Te 127.6 |
|
| 84 Po 210.0 |
|
| 116 Uuh 289.0 |
An isotope of Element 116 (292Uuh) was identified in the reaction of 248Cm with 48Ca (shown above). It is very shortlived (47 milliseconds) and decomposes to a previously identified isotope of element 114, 288114Uuq.
Various reports indicated the half-life of 292Uuh as being 47 milliseconds, 0.6 milliseconds (0.0006 seconds, and 18 milliseconds (0.018 seconds.
| 1s2 | ||||||
| 2s2 | 2p6 | |||||
| 3s2 | 3p6 | 3d10 | ||||
| 4s2 | 4p6 | 4d10 | 4f14 | |||
| 5s2 | 5p6 | 5d10 | 5f14 | |||
| 6s2 | 6p6 | 6d10 | ||||
| 7s2 | 7p4 |
On May 11, 2001, the institute reported synthesizing a second atom, and that the properties confirmed a region of "enhanced" stability.
In 2004 in the Joint Intitute for Nuclear Research the synthesis of this element was confirmed by another method.
In October, 2006 it was announced that on three occasions Californium-249 atoms had been bombarded with Calcium-48 ions to produce Ununoctium-118, which decayed to Ununhexium within a millisecond. If confirmed, the synthesis of element 116 will have been proven definitively.
Other sources report the following:
Ununhexium's most stable isotope, Ununhexium-291, has a half-life of about 18 milliseconds. It decays into Ununquadium-287 through alpha decay.
Since only a few atoms of Ununhexium have ever been produced, it currently has no uses outside of basic scientific research.
| Isotope | Atomic Mass |
Half-Life |
|---|---|---|
| 289Uuh | 289.19886 | ~10 ms |
| 290Uuh | 290.19859 | 15 ms |
| 291Uuh | 291.20001 | 6.3 ms |
| 292Uuh | 292.19979 | 18.0 ms |
| 293Uuh | 61 ms |