Unbipentium

Unbipentium is a hypothetical (theoretical or imagined) element of the periodic table. It is also known as eka-neptunium.
The atomic number of this element is 125. It has the symbol Ubp. The name Unbipentium and the symbol Ubp are temporary IUPAC names. This name and symbol exist until a permanent name is decided. It is expected to be a g-block element and an superactinides. It is the sixth element in the eighth period of the periodic table.
The synthesis of unbipentium was first attempted in 1977 by bombarding a target of Americium-238 with zinc-65 ions at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany:
No atoms were identified.