Science / Periodic Table of Elements / Ununoctium (Uuo): Atomic number: 118, Atomic mass: unknown, Electronegativity: unknown, Density: unknown, Melting point: unknown, Boiling point: unknown, Vanderwaals radius: unknown, Ionic radius: unknown, Isotopes: unknown, Discovered by: Team of Berkeley Lab scientists, 1999. Ununoctium is the temporary name of a retracted chemical element in the periodic table that has the temporary symbol Uuo and has the atomic number 118. In 1999, researchers at Lawrence Berkeley National Laboratory announced the discovery of elements 116 and 118, in a paper published in Physical Review Letters. The following year, they published a retraction after other researchers were unable to duplicate the results. In June 2002, the director of the lab announced that the original claim of the discovery of these two elements had been based on data fabricated by principal author Victor Ninov. The name Ununoctium is used as a placeholder, such as in scientific articles about the search for Element 118; it is Dog Latin 'one-one-eight-ium' ('ium' being a standard ending for element names). Such transuranic elements are always artificially produced, and usually end up being named for a scientist or the town of their discovery ?? la darmstadtium. See Element naming controversy, systematic element name. Ununoctium would probably share the properties of its group, the noble gases, resembling radon in its chemical properties. Ununoctium doesn’t occur naturally, it has not been found in the earth’s crust, so there is no reason to consider its environmental effects.