Seaborgium (Sg)

Isotopes of Seaborgium

Isotope Atomic Mass Half-life Mode of Decay Nuclear Spin Nuclear Magnetic Moment
Sg-258 258.1132 0.0029 seconds α to Rf-254; SF No data available  No data available 
Sg-259 259.1147 0.90 seconds α to Rf-255 1/2 No data available 
Sg-260 260.1144 0.0036 seconds α to Rf-256 0 No data available 
Sg-261 261.1162 0.23 seconds α to Rf-257; SF No data available  No data available 
Sg-262 262.1164 0.0008 seconds No data available  No data available  No data available 
Sg-263 263.11822 0.80 seconds α to Rf-259 No data available  No data available 
Sg-264 264.1189 0.0037 seconds No data available  0 No data available 
Sg-265 265.1211 16.00 seconds α to Rf-261 No data available  No data available 
Sg-266 266.1219 21.00 seconds α to Rf-262; SF No data available  No data available 


Seaborgium is a synthetic element (an element that can be created in a laboratory but is not found in nature) discovered in 1974 by Albert Ghiorso and others at the Lawrence Berkeley National Laboratory and the Livermore National Laboratory, California, USA. Seaborgium takes its name from Glenn T. Seaborg, American nuclear chemist and Nobel Prize winner.

Chemistry experiments with seaborgium have firmly placed it in group 6 as a heavier homologue to tungsten. In its aqueous chemistry, seaborgium has been shown to resemble molybdenum and tungsten.

Properties of Seaborgium

Name Seaborgium
Symbol Sg
Atomic number 106
Atomic weight [271]
Standard state Presumably a solid at 298 °K
CAS Registry ID 54038-81-2
Group in periodic table 6
Group name None
Period in periodic table 7
Block in periodic table d-block
Color Unknown, but probably metallic and silvery white or grey in appearance
Classification Metallic
Melting point No data available
Boiling point No data available
Density of solid 23.2 g/cm3 (predicted)
Electron configuration [Rn]5f146d47s2
Oxidation state +6

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