New Names for Elements 114 and
116
Scientists of the Lawrence Livermore National Laboratory (LLNL)-Dubna collaboration proposed the names as Flerovium for element 114, with the symbol Fl, and Livermorium for element 116, with the symbol Lv, late last year.The International Union of Pure and Applied Chemistry (IUPAC) officially approved new names for elements 114 and 116, the latest heavy elements to be added to the periodic table, on May 31, 2012. See IUPAC news ite
Flerovium (atomic
symbol Fl) was chosen to honor Flerov Laboratory of Nuclear Reactions, where
superheavy elements, including element 114, were synthesized. Georgiy N. Flerov
(1913-1990) was a renowned physicist who discovered the spontaneous fission of
uranium and was a pioneer in heavy-ion physics. He is the founder of the Joint
Institute for Nuclear Research. In 1991, the laboratory was named after Flerov
-- Flerov Laboratory of Nuclear Reactions (FLNR).
Livermorium (atomic
symbol Lv) was chosen to honor Lawrence Livermore National Laboratory (LLNL)
and the city of Livermore, Calif. A group of researchers from the Laboratory,
along with scientists at the Flerov Laboratory of Nuclear Reactions, participated
in the work carried out in Dubna on the synthesis of superheavy elements,
including element 116. (Lawrencium -- Element 103 -- was already named for
LLNL's founder E.O. Lawrence.)
The IUPAC states
Livermorium was chosen because over the years scientists at Livermore have been
involved in many areas of nuclear science: the investigation of fission
properties of the heaviest elements, including the discovery of bimodal
fission, and the study of prompt gamma-rays emitted from fission fragments
following fission; the investigation of isomers and isomeric levels in many
nuclei; and the investigation of the chemical properties of the heaviest
elements.
"These names
honor not only the individual contributions of scientists from these
laboratories to the fields of nuclear science, heavy element research, and
superheavy element research, but also the phenomenal cooperation and
collaboration that has occurred between scientists in these two
countries," said Bill Goldstein, associate director of LLNL's Physical and
Life Sciences Directorate.
Scientists at LLNL
have been involved in heavy element research since the Laboratory's inception
in 1952 and have been collaborators in the discovery of six elements --
113,114,115,116,117 and 118.
Livermore also has
been at the forefront of investigations into other areas related to nuclear
science such as cross-section measurements, nuclear theory, radiochemical
diagnostics, separations chemistry including rapid automated aqueous
separations, actinide chemistry, heavy-element target fabrication and nuclear
forensics.
HOW THEY ARE CREATED
The creation of
elements 116 and 114 involved smashing calcium ions (with 20 protons each) into
a curium target (96 protons) to create element 116. Element 116 decayed almost
immediately into element 114. The scientists also created element 114
separately by replacing curium with a plutonium target (94 protons).
The creation of
elements 114 and 116 generate hope that the team is on its way to the
"island of stability," an area of the periodic table in which new
heavy elements would be stable or last long enough for applications to be
found.
The official names
will be published in the July issue of the IUPAC journal, Pure and Applied
Chemistry.
The process of
discovery and naming of an element is a long one. Experiments first glimpsed
element 114 in 1998 and element 116 in 2001, with continuing experiments
satisfying the discovery criteria in 2004 and 2006, and confirmatory
experiments by other laboratories in 2007 – 2010.
The collaboration is
led by Dr. Yuri Ts. Oganessian. The participants in these experiments include:
Dubna: Yu.Ts. Oganessian, V.K. Utyonkov, F.Sh. Abdullin, A.N. Polyakov, I.V. Shirokovsky, Yu.S. Tsyganov, R.N. Sagaidak, G.G. Gulbekian, S.L Bogomolov, B.N. Gikal, A.N. Mezentsev, V.G. Subbotin, A.M. Sukhov, A.A. Voinov, K. Subotic, G.K. Vostokin, M.G. Itkis, V.I. Zagrebaev, R.I. Il’kaev, S.P. Vesnovskii
LLNL: K.J. Moody, D.A. Shaughnessy, M.A. Stoyer, J.M. Kenneally, C.A. Gregorich, J.H. Landrum, R.W. Lougheed, J.B. Patin, N.J. Stoyer, J.F. Wild, and P.A. Wilk
Dubna: Yu.Ts. Oganessian, V.K. Utyonkov, F.Sh. Abdullin, A.N. Polyakov, I.V. Shirokovsky, Yu.S. Tsyganov, R.N. Sagaidak, G.G. Gulbekian, S.L Bogomolov, B.N. Gikal, A.N. Mezentsev, V.G. Subbotin, A.M. Sukhov, A.A. Voinov, K. Subotic, G.K. Vostokin, M.G. Itkis, V.I. Zagrebaev, R.I. Il’kaev, S.P. Vesnovskii
LLNL: K.J. Moody, D.A. Shaughnessy, M.A. Stoyer, J.M. Kenneally, C.A. Gregorich, J.H. Landrum, R.W. Lougheed, J.B. Patin, N.J. Stoyer, J.F. Wild, and P.A. Wilk
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