Rutherfordium (Rf). Diagram of the nuclear composition and electron configuration of an atom of rutherfordium-263 (atomic number: 104), the most stable isotope of this radioactive element. The nucleus consists of 104 protons (red) and 159 neutrons (blue). Named after Ernest Rutherford and first synthesised in 1968, it is a transactinide and transition metal in group 4, period 7, and the d-block of the periodic table. Rutherfordium-263 has a half-life of 15 minutes, its nucleus emitting an alpha particle to form nobelium-259.
Model release not required. Property release not required.