Russia, Germany and Japan are preparing for the synthesis of elements 119 and 120


    Periodic table of chemical elements (at the beginning of 2018)

    This year, the Laboratory of Nuclear Reactions named after G.N. Flerov at the Joint Institute for Nuclear Research (JINR) in Dubna will launch a new accelerator complex - the Superheavy Elements Factory. This complex will become the basis for the synthesis of new chemical elements.

    “We are preparing for the synthesis of the first two elements of the eighth period - the 119th and 120th. We are planning to start the corresponding experiments in 2019, ”thescientific secretary of the Laboratory of Nuclear Reactions of JINR Alexander Karpov told Izvestia.

    It was in Dubna at the U-400 accelerator complex that the 113th element was discovered (nihonium, Nh, turned out as a by-product during the synthesis of the 115th element), the 115th (Muscovy, Mc), the 117th (Tennesin, Ts) and 118th (oganeson, Og).

    The latter element is named in honor of the academician Yuri Oganesyan who opened it. The penultimate - in honor of the state of Tennessee, for the contribution of this state, including the Oak Ridge National Laboratory, Vanderbilt University and the University of Tennessee in Knoxville, in the study of superheavy elements.

    Now the periodic table of chemical elements ends with just the 118th element. At present, the only known nuclide of the element is 294 Og with a half-life of 1 ms and an atomic mass of 294.214 (5). eat.

    Of course, the artificially synthesized radioactive element 118 is not found in nature. Similarly, the new elements 119 and 120, which are going to be synthesized in Dubna, are not found. In general, there are no elements in nature whose atomic numbers exceed 94. Transuranium elements are produced artificially and are usually named after scientists or at the location of the laboratory that received the element.

    Element 119 is now provisionally tentatively named Ununen (Uue), and element 120 is unbinily (Ubn). According to the rules for naming new elements adopted by the International Union of Pure and Applied Chemistry (IUPAC) in 2002, to ensure linguistic uniformity, all new elements must be given names ending in "-ium". The name is formed from the roots of Latin numerals and literally means something like "one-one-seventh." Later, after confirming the discovery, the name is changed to permanent.

    The synthesis of ununification (it is also eka-france) will be a significant event for science. The fact is that the element with atomic number 119 and the predicted atomic mass of 316 a. that is, after its synthesis, it will become the first element in the eighth period of the periodic table of chemical elements.

    An attempt to synthesize element 119 was undertaken in 1985 by bombarding a target from Einsteinium-254 with calcium-48 nuclei at the SuperHILAC accelerator at Berkeley. Unfortunately, not a single atom could be identified .

    In addition to Russian physicists from JINR, experiments on the synthesis of element 119 are now being prepared at the Helmholtz Center for the Study of Heavy Ions (Germany) and the Institute of Physical and Chemical Research (RIKEN, Japan). So, to obtain the 119th element, Japanese scientists are going to combine the nuclei of the 23rd element of vanadium and the 96th element of curium , and to obtain the 120th element - the nucleus of the same curium and the 24th element - chromium. For the synthesis, a particle accelerator and a gas discharge ion separator upgraded specifically for this purpose are used.

    It is assumed that the ununenium will be a chemically active alkali metal, following France in the group, and will repeat most of the properties of lighter analogues. But it is expected that at the same time he will show some specific chemical properties, which are inherent only in him and are not inherent in lighter analogues.

    According to the theoretical calculations of chemists, the ununennium in chemical properties will presumably look more like rubidium or potassium than cesium or francium, ignoring the tendency for an element to increase in chemical activity as the serial number increases.

    The new accelerator complex in Dubna will allow an increase in the number of superheavy nuclei obtained by about 20–50 times compared with today's capabilities: “These nuclei are unstable, and statistics, that is, the number of atoms produced, are very important for studying them. On the existing equipment, the experiments that we plan to do at the factory can be carried out, but they will take years, and maybe decades. The factory will be 20–50 times more efficient, the studies will fit in weeks or months, ”said Alexander Karpov.

    Synthesis of elements 119 and 120 will help to get closer to the mystery of the "island of stability" - the hypothetical region of the periodic table, where the longest-lived super-heavy nuclei are located.

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