Roentgenium is a chemical element with symbol Rg and atomic number 111. It is an extremely radioactive synthetic element (an element that can be created in a laboratory but is not found in nature); the most stable known isotope, roentgenium-282, has a half-life of 2.1 minutes. Roentgenium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany.
111 Atomic Number
282 u Atomic Mass
null K Melting Point
null K Boiling Point
28.7 g/cm³ Density
null Å Atomic Radius
null Å Covalent Radius
null eV First Ionization Energy
151 Electron Affinity
7 Number of Shells
2, 8, 18, 32, 32, 17, 2 Electron Shell Occupations
