This sounds like we will finally be able to declare element 113 asdiscovered. This work has been inching along for decades and it isalways welcome to add another unique element to the periodic table. It is even better to characterize it.
It would not surprise me to discover much higher zones of stabilityas the years go by although our ability to work with the materialwill also need to be revolutionized.
All good work and welcome to see as it has been a while.
Japanese TeamClaims Discovery Of Elusive Element 113, And May Get To Name It
The claim needs to beverified by chemical authorities, but the team says it's thestrongest evidence yet for the highly unstable element.
By RebeccaBoylePosted 09.26.2012 at 11:47 am
Decay Chain of Element113 Superheavy element 113 decays to the following daughterisotopes: Roentgenium-274; Meitnerium-270; Bohrium-266; Dubnium-262;Lawrencium-258; and Mendelevium-254.RIKEN http://www.popsci.com/science/article/2012-09/japanese-team-claims-discovery-elusive-element-113-and-may-get-name-it Japanese researchersclaim they’ve seen conclusive evidence of the long-sought element113, a super-heavy, super-unstable element near the bottom of theperiodic table. It’s not yet verified by the International Union ofPure and Applied Chemistry, which regulates the table and the namesof the elements — but if the IUPAC grants its blessing, theresearchers could be the first team from Asia to name one of nature’sfundamental atoms.
Super-heavy elementsdo not occur in nature and have to be discovered in the lab,using particle accelerators, nuclear reactors, ion separatorsand other complex equipment. Scientists led by Kosuke Morita at theRIKEN Nishina Center for Accelerator-based Science have been huntingfor 113 for nine years, and have claimed to see it a few timesalready — but the evidence has never been this clear, the team saidtoday.
In an experiment inAugust, the team used a customized gas-filled recoil ion separatorpaired with a semiconductor detector that can pick out atomicreaction products. They created element 113 by speeding zinc ionsthrough a linear accelerator until they reached 10 percent of thespeed of light. The ions then smashed into a piece of bismuth. Whenthe zinc and bismuth atoms fused, they produced an atom with 113protons. This atom decayed, incredibly rapidly, into a series ofdaughter products, each an alpha particle (two protons and twoneutrons) lighter than the parent atom. The daughter nuclides arethe clear offspring of element 113, and only element 113,whose presence can thus be determined.
Back in 2004 and 2005,the same team noticed what looked like element 113 in four decayevents, which included the spontaneous fission of an isotope ofdubnium (element 105). But the final daughter products were notestablished relatives of 113, so the IUPAC didn’t recognize thediscovery. This time, the alpha decay chain is clearer: From a heavyisotope of element 113, to isotopes of relatives Roentgenium (111);Meitnerium (109); Bohrium (107); Dubnium (105); Lawrencium (103); andMendelevium (101).
A new paper describingthis decay chain will be published in the Journal of thePhysical Society of Japan. Representatives of the IUPAC have not yetresponded to a request for comment on what’s next.
The periodic tableis almost full. During the past few years, teams in variouscountries have reported finding the final remaining elements: 113,115, 117 and 118. As of June, the IUPAC was stillevaluating claims for their discovery. No assignments have been madeyet, but are being considered by a IUPAC and IUPAP Joint WorkingParty. If the IUPAC recognizes this discovery, the RIKEN team willget to name element 113.
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