New Elements Added to Periodic Table

Discovery and Assignment of Elements with Atomic Numbers 113, 115, 117 and 118

Element117-e1451941953387
An artist’s illustration shows element 117, which has now been officially added to the periodic table of the elements. Kwei-Yu Chu/LLNL

It is only fitting that today, the day that the world celebrates Isaac Newton’s birthday, January 4th, 1643, that announcement has been made that 4 new elements have been added to the Periodic Table. The addition of these 4 new elements completes the seventh period in the Periodic Table of the Elements according to the International Union of Pure and Applied Chemistry. These new elements have atomic numbers 113, 115, 117 and 118 and will get permanent names soon, according to the IUPAC. As of now, the working names for two of the four new elements whose discovery has been officially verified are ununseptium and ununtrium.

 

Said IUPAC President Dr. Mark C. Cesa:

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, the International Union of Pure and Applied Chemistry is pleased and honored to make this announcement concerning elements 113, 115, 117, and 118 and the completion of the seventh row of the periodic table of the elements

Dr. Cesa went on to say

…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.

These new additions come nearly five years after elements 114 (flerovium, or Fl) and element 116 (livermorium or Lv) were added to the table.

IUPAC announces the verification of the discoveries of four new chemical elements: The 7th period of the periodic table of elements is now complete.

Thursday, Dec. 31, 2015
Ecstatic, Kosuke Morita of the Riken Nishina Center for Accelerator-Based Science points at periodic table of the elements during a press conference in Wako, Saitama prefecture, near Tokyo.

The fourth IUPAC/IUPAP Joint Working Party (JWP) on the priority of claims to the discovery of new elements has reviewed the relevant literature for elements 113, 115, 117, and 118 and has determined that the claims for discovery of these elements have been fulfilled.

In announcing the new elements, Paul Karol, chair of the IUPAC’s Joint Working Party, a group that includes members of the International Union of Pure and Applied Physics, discuses the difficulties involved in founding a new elements.

A particular difficulty in establishing these new elements is that they decay into hitherto unknown isotopes of slightly lighter elements that also need to be unequivocally identified…but in the future we hope to improve methods that can directly measure the atomic number, Z.

In accordance with the 1991 discovery criteria for elements established by the IUPAP/IUPAC Transfermium Working Group (TWG), the fourth IUPAC/IUPAP Joint Working Party (JWP), on the priority of claims to the discovery of new elements, has reviewed the relevant literature for elements 113, 115, 117, and 118. It is their determination that the criteria regarding the discovery of new elements in this case have been fulfilled. The collaborators from Japan, Russia and the USA will now be invited to suggest permanent names and symbols for the four “new” elements.

Element 113 (temporary working name and symbol: ununtrium, Uut)
The RIKEN collaboration team in Japan have fulfilled the criteria for elementZ=113 and will be invited to propose a permanent name and symbol.

Elements 115, 117, and 118 (temporary working names and symbols: ununpentium, Uup; ununseptium, Uus; and ununoctium, Uuo)
The collaboration between the Joint Institute for Nuclear Research in Dubna, Russia; Lawrence Livermore National Laboratory, California, USA; and Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA have fulfilled the criteria for element Z=115, 117 and will be invited to propose permanent names and symbols.

1451925255113
The seventh period of the periodic chart is now complete, thanks to the addition of four new elements. IUPAC

Regarding naming of the new elements, Professor Jan Reedijk, President of the Inorganic Chemistry Division of IUPAC had this to say

The chemistry community is eager to see its most cherished table finally being completed down to the seventh row. IUPAC has now initiated the process of formalizing names and symbols for these elements temporarily named as ununtrium, (Uut or element 113), ununpentium (Uup, element 115), ununseptium (Uus, element 117), and ununoctium (Uuo, element 118).

In a December 30th, 2015, lengthy-worded press release, the IUPAC (International Union of Pure and Applied Chemistry), describes the international scientific community’s enthusiasm for the finding and the ensuing process of choosing a name for the new elements.

In the press release, IUPAC President Dr. Mark C. Cesa describes the importance and significance of this find

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, the International Union of Pure and Applied Chemistry is pleased and honored to make this announcement concerning elements 113, 115, 117, and 118 and the completion of the seventh row of the periodic table of the elements

Dr. Cesa goes on to say that

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.

Relevance to Astronomy
One may wonder about the relevance of this topic to astronomy. All the baryonic matter in the universe, all the matter that we can see or interact with, was produced in the first 17 minutes following the primordial inflationary event (the Big Bang). In other words, all that we see, interact with or measure was synthesized in the first 17 minutes of creation. After that, the super-hot plasma had cooled below the threshold necessary for nucleosynthesis to occur. What remained was the Primordial Abundance, the fuel for the first stars: 73% Hydrogen by volume, 25% Helium and 2% light metals (Beryllium and Boron). Since then the concentration of that initial abundance is being slowly altered, inexorably reducing the overall hydrogen abundance throughout the universe through stellar nucleosynthesis. The universe will ultimately suffer a heat death; so, the answer to the age-old question, will the universe die by fire or ice, it will be by ice. Still, what does this have to do with the announcement by the IUPAC?

star2evo
The evolutionary paths of low mass through high mass stars

All stars derive their energy through nuclear fusion, the transmutation of four hydrogen nuclei (protons) into a helium nucleus. For lower-mass stars like our sun, after all but 12% of the star’s core hydrogen has been depleted, during the star’s helium burning phase, the process will continue through a series of core contractions, heating and expansions, with the transmutation of 3 helium nuclei to form a Carbon-12 nucleus. This process, by which the transmutation of helium into carbon occurs, is known as the Triple-Alpha process, a 2-step nuclear fusion process that ultimately combines 3 He4 nuclei (alpha particles) to form a stable Carbon-12 nucleus; this is the only means by which carbon is produced and is the nuclear dead-end for solar class stars.

HyperNova_HeavyElementProduction
An artists rendering of the layered, heavy-element rich core of a high-mass star as it self-destructs in a violent Type-II supernova. The stellar remnant, if one still remains, may become a pulsar (a rapidly rotating neutron star) or a black hole.

For higher mass stars greater than 8 solar masses, the process continues, terminating in a silicon burning cycle that produces heavy metals up to and including Iron and Nickel. Since the “iron group” is at the top of the binding energy curve, fusion of elements above iron dramatically absorb energy and no additional alpha particles (helium nuclei – this is what’s been happening: the addition of an alpha particle to each successive element, known as Helium capture, to produce the next element in the series) can be added to Nickel to produce the next element in the chain, a Zn-60 (Zinc) nucleus and the process ends here – for all stars; this is the nuclear dead-end for all stars, of any mass. The end result is an implosion of the degenerate Nickel-Iron inner-core and a Type II, core-collapse supernova.

Still, no answer as to why all this is relevant to the announcement by the IUPAC.

If the production of heavy elements ends with Iron and Nickel how can we account for the heavier elements following Nickel (Copper, Zinc, etc) and the remainder of the Periodic Table? The release of all the pent-up gravitational potential energy in the tiny, degenerate stellar core as a Type-II supernova is so titanic and so enormous that the flood of heavy nuclei streaming away from the destroyed star freely combine with the torrent of free neutrons now available. Since neutrons are electrically neutral there is no electrostatic repulsion and they combine with the flood of heavy-element isotopes in a flurry of heavy-element genesis up through and including uranium, the heaviest of the naturally-occurring elements. This process is known as Rapid Neutron Capture (R-Capture) and is one of two processes that produce elements heavier than Iron, Cobalt and Nickel (the Iron Group); the other is more of a slow-cooker process with time scales measured in thousands of years compared to seconds for the R-Capture process. This latter process, S-Capture, is thought to occur in highly-evolved, AGB (Asymptotic Giant Branch) stars in time scales measured in millennia while R-Capture occurs within seconds in explosive environments, such as in supernovae. In either case, beta-minus decay in the newly formed heavy isotope transmutes the captured neutron into a proton, yielding an isotope with a greater atomic number (the number of protons contained in the nucleus).

As a final piece to this and something that is at the heart of the increasing instability with increasing atomic number as evidenced and presented in the IUPAC announcement, the heavier the nucleus, the larger the atomic radius and thus, the weaker the binding force holding it together. The Strong Nuclear Force, the force that binds the nucleus together, is strong over distances small relative to the radius of heavy nuclei, thus the inherent instability of increasingly large, relatively heavy nuclei. This is the key reason why there is an upper limit to atomic mass and atomic number, that there cannot be arbitrarily heavy nuclei: the nucleus will simply decay to smaller, more stable nuclei.

Finally, I would suggest that “discovery” is not the correct term to describe this finding. Since all elements heavier than uranium are synthesized, they are not really “discovered” in the conventional sense as occurring in nature, but rather are produced or created in a controlled, laboratory environment.

Imagination is more important than knowledge585px-Albert_Einstein_signature_1934(invert)
An index of all articles in this blog can be found here.

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9 thoughts on “New Elements Added to Periodic Table

  1. Patting themselves on the back for chasing a chimera that barely exists.
    As climate change bites and antibiotics reach their expiry date the worlds leading brains concentrate their united efforts on the periodic table filling in the unfillable.
    Still we have learnt a most useful fact in the unimaginable future global warming will be cooled down by an icey death.

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    1. Yes, very well put! In fact, to call it a discovery is actually inaccurate and is something I alluded to in the post. They discovered nothing since these 4 new elements *don’t* occur in nature. All they did was build a nucleus with a new atomic number that remained stable over a given time frame. *All* nuclei heavier than Uranium were never *discovered*, but simply synthesized in the lab. Agree with you too, re: antibiotics and climate change!
      Cheers!
      TM

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      1. This is true; science, in general, is regarded as an opinion by many and, as such, opinions can be disregarded. Said differently since science is regarded my many as an opinion, opinions can be regarded almost as an individual’s theory unto themselves. The problem with this is that many act on their theory, believing it to be true. We see this regarding climate change and this is at the crux of that problem. Individuals do what they want, essentially acting on their own scientific theory unto themselves. Problem here is that their actions have consequences. World leaders and governments need to be informed by science and academia not whims and half-baked “theories” of pseudo-scientists. This underscores the need for excellence in education in the STEM fields and national agencies in every government that support this.

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