Rutherfordium 104th chemical element, symbol Rf.
There was a dispute as to what the elements with atomic numbers from 101 to 109 were to be called; Since it was detected in 1964 by workers at the Joint Nuclear Research Institute at Dubna (U.S.S.R.), Dubium (Db) was suggested, as was Kurchatovium and symbol Ku for element 104, in honor of Igor Vasilevich Kurchatov (1903-1960), former Head of Soviet Nuclear Research. The International Union of Pure and Applied Physics (IUPAC) adopted Unnilquadium (symbol Unq) as a temporary name for this element. However in 1997 they resolved the dispute and adopted the current name.
See: Periodic table