| Element 118
CAS: Description: Classification: Transactinide Date of Discovery: April, 1999 Discoverer: Ken Gregorich, Lawrence Berkeley National Laboratory Name Origin: |
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Atomic Number: 118
Number of Neutrons: 175 Atomic Mass: (293) Melting Point: Boiling Point: Density (293 K): Atomic volume: Electrical resistivity: Thermal conductivity: Enthalpy of atomization: Enthalpy of vaporization: Enthalpy of fusion: Specific heat capacity: |
Energy levels:
Electron configuration: [Rn]5f 146d107s27p6 (?) Crystal Structure: Atomic radius: Covalent radius: Oxidation States: Electronegativity, Pauling: Electron affinity: First ionization energy: 2nd ionization energy: 3rd ionization energy: Polarizability: |
| Isotope | Atomic Mass | Half-life | Decay Mode | Spin |
| 293118 | <1 ms |  |
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Element 118 was discovered at Lawrence Berkeley Lab in April, 1999, by accelerating a beam of krypton-86 ions to an energy of 449 million electron volts and directing the beam into targets of lead-208. The discovery of is based on the scientists' observations of three separate decays of the elements in the 88-inch cyclotron. Magnetic focussing by
the Berkeley Gas-Filled Separator allowed separation and implantation into a silicon detector of the three detectable atoms of element 118 that have nuclei possessing 118 protons and 175 neutrons for a mass total of 293. The new elements are even further along in the Periodic Table than element 114, whose existence was announced back in January 1999 by scientists in Russia, and further into the "island of stability," the supposed nuclear regime in which certain combinations of neutrons and protons lead to a relatively long life. For all that, the atoms of element 118 still decay after less than a millisecond into element 116 plus an alpha particle. Element 116 then promptly decays into element 114 plus another alpha particle. Ken Gregorich led the LBL group that discovered the new nuclei. Four of the team members are German nationals, which prompted DOE secretary Bill Richardson to emphasize the continuing value of international scientists working at US national labs.
LINKS: Physicists at Cal find heaviest elements (6/7/99) Two New Superheavy Elements Discovered (6/8/99) Two New Superheavy Elements Discovered At Berkeley Lab (6/8/99 - same artticle as above) Discovery of 2 new artificial elements excites researchers (6/9/99) It’s Not Heavy, It’s My Element (6/9/99) Discovery of Elements 118 and 116 (6/10/99) Return
Sources for the information on this website include: Lide, David R., ed. CRC Handbook of Chemistry and Physics, 78th Ed., 1997-1998. |
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