livermorium, artificially produced radioactive chemical element; symbol Lv; at. no. 116; mass number of most stable isotope 292; m.p., b.p., sp. gr., and valence unknown. Situated in Group 16 of the periodic table, it is expected to have properties similar to those of polonium and tellurium.
In 1999 a research team at the Lawrence Berkeley National Laboratory in Calif. bombarded lead-208 atoms with high-energy krypton-86 ions to create, apparently, ununoctium (element 118) atoms. The Uuo-293 isotope that they synthesized emitted an alpha particle to decay into Lv-289, which has a life-life of about 0.6 millisecond, which then emitted an alpha particle to decay into flerovium (element 114). Although the Berkeley laboratory retracted its claim for creating ununoctium in 2001, other research teams have since created livermorium directly. In 2011 its creation was officially confirmed, based on work in 2004 and 2006 by Lawrence Livermore National Laboratory in Calif. and the Joint Institute for Nuclear Research in Dubna, Russia. Using isotopes provided by Livermore, the Dubna facility bombarded curium-245 with calcium-48 to produce Lv-291. The name livermorium, after the Livermore laboratory, was proposed (2011) for the element and adopted by the International Union of Pure and Applied Chemistry (IUPAC) in 2012.
See also synthetic elements; transactinide elements; transuranium elements.