Periodic Table of Elements




Rutherfordium was first discovered in 1964 at the Joint Institute of Nuclear Research at Dubna, Russia by bombarding a plutonium-242 target with neon-22 ions.

Name: Rutherfordium
Symbol: Rf
Atomic number: 104
Atomic weight: 265.12
State: solid presumably
Group, period, block: 4, 7, d
Color: unknown
Classification: transition metal
Electron configuration: 5f14 6d2 7s2[1][2]

Physical properties

Density: 23 g/cm-3
Melting point: 2400 K,2100 C,3800 (estimated)[1][2] F
Boiling point: 5800 K,5500 C,9900 (estimated)[1][2] F

Atomic properties

Oxidation states: 4,[1] 3 (predicted)[2]
Electronegativity: no data
Ionization energies: 1st: 579.9 (estimated)[2] kJmol-1
Covalent radius: 157 (estimated)[1] pm
Van der Waals radius: 187 pm
  • Rf
  • Electron Configuration


Rutherfordium has no stable or naturally-occurring isotopes. Several radioactive isotopes have been synthesized in the laboratory.