Ununtrium

Ununtrium (pronounced /uːnˈuːntri.əm/ ( listen) oon-OON-tree-əm) is the temporary name of a synthetic element with the temporary symbol Uut and atomic number 113. It is placed as the heaviest member of the group 13 (IIIA) elements although a sufficiently stable isotope is not known at this time that would allow chemical experiments to confirm its position. It was first detected in 2003 in the decay of element 115 and was synthesized directly in 2... more

Ununtrium (pronounced /uːnˈuːntri.əm/ ( listen) oon-OON-tree-əm) is the temporary name of a synthetic element with the temporary symbol Uut and atomic number 113. It is placed as the heaviest member of the group 13 (IIIA) elements although a sufficiently stable isotope is not known at this time that would allow chemical experiments to confirm its position. It was first detected in 2003 in the decay of element 115 and was synthesized directly in 2004. Only eight atoms of ununtrium have been observed to date. The longest-lived isotope known is 113 with a half-life of ~500 ms. The first report of ununtrium was in August 2003 when it was identified as a decay product of ununpentium. These results were published on February 1, 2004, by a team composed of Russian scientists at Dubna (Joint Institute for Nuclear Research), and American scientists at the Lawrence Livermore National Laboratory. On July 23, 2004, a team of Japanese scientists at RIKEN detected a single atom of Uut using the... less