scholarly journals Synthesis and Study of the New Superheavy Elements of D.I. Mendeleev Periodic Table of the Elements

Vestnik RFFI ◽  
2019 ◽  
pp. 87-104
Author(s):  
Yuri Ts. Oganessian
Keyword(s):  
Periodic Table ◽  
Nuclear Reactions ◽  
Chemical Properties ◽  
Nuclear Research ◽  
Superheavy Elements ◽  
Fusion Reactions ◽  
Flerov Laboratory ◽  
The Sixties ◽  
Experimental Complex ◽  
Physical And Chemical

In the sixties of the XX century, the possibility of existence of the region of increased stability of superheavy nuclei in the vicinity of Z | 114 and N | 184 was proved. For the first time a successful synthesis of superheavy elements was carried out in the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research (JINR). Superheavy elements of D.I. Mendeleev Periodic Table of the Elements with atomic numbers 114–118 were synthesized in the fusion reactions of the nuclei of the transuranic elements with calcium-48 nuclei. The article deals with the choice of reactions for the synthesis of new elements, methods of studying their nuclear-physical and chemical properties. The experimental complex “Factory of superheavy elements” created in JINR and prospects of further research development are described.

scholarly journals Superheavy elements

2019 ◽  
Vol 89 (6) ◽  
pp. 563-570
Author(s):  
Yu. Ts. Oganessian
Keyword(s):  
Periodic Table ◽  
Nuclear Reactions ◽  
Nuclear Research ◽  
Superheavy Elements ◽  
Superheavy Nuclei ◽  
Fusion Reactions ◽  
Nuclear Theory ◽  
Oak Ridge ◽  
Flerov Laboratory ◽  
Heaviest Elements

Synthesis of superheavy elements predicted by microscopic nuclear theory is investigated. The heaviest elements with Z = 114–118 were synthesized by fusion reactions of actinide nuclei with 48Ca ions accelerated using the U-400 complex at the Flerov Laboratory of Nuclear Reactions (FLNR), one of seven laboratories that comprise the Joint Institute for Nuclear Research (JINR) located in Dubna, Russia. The experiments were carried out in collaboration with physicists and chemists working at the Livermore and Oak Ridge national laboratories in located in California and Tennessee, respectively. Discovery of these elements allowed completion of the seventh period of the periodic table. The microscopic nuclear theory’s fundamental predictions about the possible existence of superheavy elements received the experimental confirmation. A new laboratory, i.e., the "STE Factory" associated with the JINR FLNR, has been established to research superheavy nuclei.

scholarly journals Chemistry of the superheavy elements

2015 ◽  
Vol 373 (2037) ◽  
pp. 20140191 ◽  
Author(s):  
Matthias Schädel
Keyword(s):  
Periodic Table ◽  
Nuclear Reactions ◽  
Noble Gas ◽  
Relativistic Quantum ◽  
Chemical Properties ◽  
Relativistic Effects ◽  
Electron Shell ◽  
Heavy Ion ◽  
Superheavy Elements ◽  
Shell Effects

The quest for superheavy elements (SHEs) is driven by the desire to find and explore one of the extreme limits of existence of matter. These elements exist solely due to their nuclear shell stabilization. All 15 presently ‘known’ SHEs (11 are officially ‘discovered’ and named) up to element 118 are short-lived and are man-made atom-at-a-time in heavy ion induced nuclear reactions. They are identical to the transactinide elements located in the seventh period of the periodic table beginning with rutherfordium (element 104), dubnium (element 105) and seaborgium (element 106) in groups 4, 5 and 6, respectively. Their chemical properties are often surprising and unexpected from simple extrapolations. After hassium (element 108), chemistry has now reached copernicium (element 112) and flerovium (element 114). For the later ones, the focus is on questions of their metallic or possibly noble gas-like character originating from interplay of most pronounced relativistic effects and electron-shell effects. SHEs provide unique opportunities to get insights into the influence of strong relativistic effects on the atomic electrons and to probe ‘relativistically’ influenced chemical properties and the architecture of the periodic table at its farthest reach. In addition, they establish a test bench to challenge the validity and predictive power of modern fully relativistic quantum chemical models.

Superheavy elements

2004 ◽  
Vol 76 (9) ◽  
pp. 1715-1734 ◽  
Author(s):  
Yu. Ts. Oganessian
Keyword(s):  
Nuclear Reactions ◽  
Chemical Elements ◽  
Magic Nucleus ◽  
Superheavy Elements ◽  
Nuclear Chemistry ◽  
Fusion Reactions ◽  
Spherical Shells ◽  
Flerov Laboratory ◽  
Theoretical Predictions ◽  
Chemistry Division

One of the fundamental outcomes of nuclear theory is the predicted existence of increased stability in the region of unknown superheavy elements. This hypothesis, proposed more than 35 years ago and intensively developed during all this time, significantly extends the limits of existence of chemical elements. “Magic ”nuclei with closed proton and neutron shells possess maximum binding energy. For the heaviest nuclides, a considerable stability is predicted close to the deformed shells with Z = 108, N = 162. Even higher stability is expected for the neutron-rich nuclei close to the spherical shells with Z = 114 (possibly also at Z = 120, 122) and N = 184, coming next to the well-known “doubly magic ”nucleus 208 Pb. The present paper describes the experiments aimed at the synthesis of nuclides with Z = 113–116, 118 and N = 170–177, produced in the fusion reactions of the heavy isotopes of Pu, Am, Cm, and Cf with 48Ca projectiles.The energies and half-lives of the new nuclides, as well as those of their daughter nuclei (Z < 113) qualitatively agree with the theoretical predictions. The question, which is the nucleus, among the superheavy ones, that has the longest half-life is also considered. It has been shown that, if the lifetime of the most stable isotopes, in particular, the isotopes of element 108 (Hs), is ≥ 5 ×107 years, they can be found in natu ral objects. The experiments were carried out during 2001–2003 in the Flerov Laboratory of Nuclear Reactions (JINR, Dubna) in collaboration with the Analytical and Nuclear Chemistry Division (LLNL, Livermore).

The transuranic elements and the island of stability

2020 ◽  
Vol 378 (2180) ◽  
pp. 20190535 ◽  
Author(s):  
Kit Chapman
Keyword(s):  
Periodic Table ◽  
Nuclear Research ◽  
Superheavy Elements ◽  
Magic Numbers ◽  
Nuclear Shell Model ◽  
Theme Issue ◽  
Protons And Neutrons ◽  
Historical Developments ◽  
The University ◽  
Nuclear Shell

Since the 1930s the synthesis of nuclides too unstable to exist naturally on Earth has stretched the periodic table to 118 elements. While the lighter transuranic elements have found uses, the isotopes of those past lawrencium, the superheavy elements, are too unstable to exist outside the laboratory. In the 1970s, leading element discoverers Glenn Seaborg at the University of California, Berkeley, USA, and Georgy Flerov, at the Joint Institute for Nuclear Research in Dubna, USSR, took interest in a supposed ‘island of stability’, leading from the nuclear shell model of Maria Goeppert Mayer and Hans Jensen, and predicted elements with so-called magic numbers of protons and neutrons would be far more stable. This review shall look at the historical developments that led to the field of element discovery, the attempts to discover superheavy elements in nature based on the island of stability, and the subsequent successful synthesis of elements and the implications of their half-lives and properties. This article is part of the theme issue ‘Mendeleev and the periodic table’.

scholarly journals The periodic table – an experimenter’s guide to transactinide chemistry

2019 ◽  
Vol 107 (9-11) ◽  
pp. 865-877 ◽  
Author(s):  
Robert Eichler
Keyword(s):  
Research And Development ◽  
Gas Phase ◽  
Periodic Table ◽  
Chemical Properties ◽  
Superheavy Elements ◽  
Experimental Results ◽  
Chemical Studies ◽  
Phase Chemical

Abstract The fundamental principles of the periodic table guide the research and development of the challenging experiments with transactinide elements. This guidance is elucidated together with experimental results from gas phase chemical studies of the transactinide elements with the atomic numbers 104–108 and 112–114. Some deduced chemical properties of these superheavy elements are presented here in conjunction with trends established by the periodic table. Finally, prospects are presented for further chemical investigations of transactinides based on trends in the periodic table.

Elements of Heroism

2019 ◽  
Vol 41 (4) ◽  
pp. 34-37
Author(s):  
Suze Kundu
Keyword(s):  
Science Fiction ◽  
Periodic Table ◽  
Relative Size ◽  
Comic Book ◽  
Chemical Properties ◽  
Relative Reactivity ◽  
Physical And Chemical Properties ◽  
Fiction Writers ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract In today’s periodic table, 118 elements stand side by side, neatly arranged in rows and columns, mapping out their relative size, proudly sharing their family’s traits, and showcasing their relative reactivity and predicted behaviour in different situations. Back in 1869 when Dmitri Mendeleev devised the arrangement of elements we use to this day, there were notable gaps left for elements that had not yet been discovered. As the arrangement of the elements was based on a range of physical and chemical properties, it was easy to predict some of the properties of the missing elements. It was in these gaps that both scientists and artists alike dared to dream about elemental discoveries with both predicted and unpredicted properties. Comic book and science fiction writers in particular had fun postulating some of the possible elements that would give their superheroes the characteristics they required to carry out their tasks. They created fictional elements in place of some of the as yet undiscovered elements, many of which now share properties with elements that exist today.

scholarly journals Model Equation Based on the 8 Groups and the 7 Periods in the Periodic Table of Elements

2021 ◽  
Vol 9 (2) ◽  
pp. 14
Author(s):  
Orwa Houshia ◽  
Harbi Daraghmeh ◽  
Naba Abuhafez ◽  
Ahmad Abdelraouf Jrar
Keyword(s):  
Periodic Table ◽  
Model Equation ◽  
Nuclear Charge ◽  
Chemical Properties ◽  
Far Right ◽  
Atomic Size ◽  
Naturally Occurring ◽  
Or Groups ◽  
Physical And Chemical ◽  
And Chemical Properties

The periodic table of chemistry contains all synthetic and naturally occurring elements. The elements are arranged in seven horizontal periods from left to right with increasing atomic number. The periodic table is divided into two groups: metals and nonmetals, within elements moving from left to right, the elements get less metallic, culminating in nonmetals on the far right side of the table. Further, the elements are also arranged in eight vertical columns or groups for those with similar physical and chemical properties. A model equation has been developed based on the 8-group and the 7-periods from which trends of elements has been calculated. Among the trends in the periodic table that were calculated are ionization energy, atomic size and effective nuclear charge. It has been discovered that the calculated theoretical values from the model equation rhyme well with the actual values for each element with few exceptions.

Relativity in the electronic structure of the heaviest elements and its influence on periodicities in properties

2019 ◽  
Vol 107 (9-11) ◽  
pp. 833-863 ◽  
Author(s):  
Valeria Pershina
Keyword(s):  
Periodic Table ◽  
Chemical Properties ◽  
Relativistic Effects ◽  
Experimental Investigations ◽  
Close Link ◽  
Chemical Studies ◽  
Heaviest Elements ◽  
Chemical Groups ◽  
Physical And Chemical ◽  
And Chemical Properties

AbstractTheoretical chemical studies demonstrated crucial importance of relativistic effects in the physics and chemistry of superheavy elements (SHEs). Performed, with many of them, in a close link to the experimental research, those investigations have shown that relativistic effects determine periodicities in physical and chemical properties of the elements in the chemical groups and rows of the Periodic Table beyond the 6thone. They could, however, also lead to some deviations from the established trends, so that the predictive power of the Periodic Table in this area may be lost. Results of those studies are overviewed here, with comparison to the recent experimental investigations.

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