The 7th period of the periodic table now has four new elements: element 113 (temporarily named as Ununtrium, or Uut), element 115 (Ununpentium, or Uup), element 117 (Ununseptium, or Uus), and element 118 (Ununoctium, or Uuo), says a group of experts from the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP).
“As the global organization that provides objective scientific expertise and develops the essential tools for the application and communication of chemical knowledge for the benefit of humankind, IUPAC is pleased and honored to make this announcement concerning elements 113, 115, 117, and 118 and the completion of the 7th row of the periodic table of the elements,” said Dr Mark C. Cesa, President of IUPAC.
IUPAP and IUPAC experts have reviewed the relevant literature for elements 113, 115, 117, and 118 and have determined that the claims for the discovery of these elements have been fulfilled:
(i) a team of scientists from the RIKEN Nishina Center for Accelerator-based Science in Japan has fulfilled the criteria for the discovery of element with atomic number Z=113;
(iii) and the Dubna–Livermore collaboration has fulfilled the criteria for the discovery of element Z=118.
“These groups will be invited to propose permanent names and symbols,” IUPAC/IUPAP experts explained.
The decisions are detailed in two reports accepted for publication in the journal Pure and Applied Chemistry.
“The chemistry community is eager to see its most cherished table finally being completed down to the 7th row,” said Prof. Jan Reedijk, President of the Inorganic Chemistry Division of IUPAC. “IUPAC has now initiated the process of formalizing names and symbols for these elements temporarily named as Ununtrium, Ununpentium, Ununseptium, and Ununoctium.”
“We are excited about these new elements, and we thank the dedicated scientists who discovered them for their painstaking work, as well the members of the IUPAC/IUPAP Joint Working Party for completing their essential and critically important task,” Dr Cesa said.
Paul J. Karol et al. 2016. Discovery of the elements with atomic numbers Z = 113, 115 and 117. Pure and Applied Chemistry, vol. 88, no. 1
Paul J. Karol et al. 2016. Discovery of the element with atomic number Z = 118 completing the 7th row of the Periodic Table. Pure and Applied Chemistry, vol. 88, no. 1