Superheavy Final Four Get Names
End of “Unun”s…
Pending endorsement by the public and given the final stamp of approval later this year, the last four “superheavy” elements remaining tagged with Latin numerals in the Periodic Table covering the known 118 elements, will be known thereafter with their “proper” names honoring institutions and places involved in their discovery as proposed by the International Union of Pure and Applied Chemistry – IUPAC.
Superheavy elements sitting in the transactinide group starting with atomic numbers (number of protons) of 104 are all radioactive, with most of them existing for seconds or fractions of second before decaying. IUPAC considers nuclei which maintain their structure for at least 10-14 seconds (100 trillionths of a second) before decaying as elements. This is the time required for an atomic nucleus to form an electron cloud. These elements which have few practical applications if any, are produced by colliding heavy atoms in powerful accelerators to provide better insight into the structures of atoms. But scientists believe in the existence of an “island of stability” beyond these short-lived elements, comprising a range of yet-to be discovered supermassive elements with very long halflives.
Produced in very few laboratories in extremely small numbers (in the range of a few atoms),these elements which remain at the center of controversies due to conflicting claims of discovery, lengthy procedures for confirmation and different names proposed, are given provisional names derived by IUPAC from the names of Latin and Greek numerals (e.g. Element 109 – Un (1)+nil (0)+enn (9)+nium = Unilennium which was later named meitnerium to honor Lise Meitner, the Austrian physicist who co-discovered nuclear fission).
As for the last four superheavies remaining with these prefixes, IUPAC proposed Nihonium (Nh) meaning “the land of the rising sun” for element 113 (originally Ununtrium) which was discovered by a Japanese team.
The name proposed for element 115 (Ununpentium) is Moscovium (Mc) önerilen isim moskovyum (Mc) to honor the Russia’s “Joint Institute for Nuclear Research” (JINR) at Dubna near Moscow where the element was discovered with contributions from the researchers of Lawrence Livermore National Laboratory in the United States.
For the element 117 (Ununseptium), IUPAC suggested tennesine (Ts) to honor the state of Tennessee in the U.S. where Oak Ridge National Laboratory as well as the Tennessee and Vanderbilt Ubniversities which contributed to its discovery are located.
For element 118 (Ununoctium) again discovered through the cooperation of JINR and Lawrence Livermore National Laboratory, IUPAC proposed the name oganesson (Og) in honor of the pioneering work in this field by Yuri Oganessian.
If not met with “serious” objections in the five month period of public review ending in November, the suggested names can be finally approved by the IUPAC Council.
- 1. “Four new element names are on the table”, ScienceOnline, 8 June 2016
- 2. “Names recommended for elements 115, 117 and 118”,DOE/Lawrence Livermore National Laboratory, 8 June 2016
- 3. https://en.wikipedia.org/wiki/Transactinide_element