106
  Sg  
266.000000
Seaborgium

Name: Seaborgium
Symbol: Sg
Atomic Number: 106
AtomicWeight: 266.000000
Family: Transition Metals
CAS RN: 54038-81-2
Description: A synthetic element not present in nature, appearance unknown, probably metallic solid.
State (25C): Unknown (Synthetic)
Oxidation states:
Valence Electrons: 6d47s2

Boiling Point:  unknown
Melting Point:
unknown
Electrons Energy Level: 2, 8, 18, 32, 32, 12, 2
Isotopes: 16 + None Stable
Heat of Vaporization: unknown
Heat of Fusion: unknown
Density: unknown
Specific Heat: unknown
Atomic Radius: unknown
Ionic Radius: unknown
Electronegativity: unknown
1s2 2s2p6 3s2p6d10 4s2p6d10f14 5s2p6d10f14 6s2p6d4 7s2

History

Element 106 was discovered almost simultaneously by two different laboratories.   In June 1974, an American research team led by Albert Ghiorso at the Lawrence Radiation Laboratory at the University of California, Berkeley reported creating an isotope with mass number 263, four free neutrons and a half-life of 1.0 second by bombarding atoms of  249Californium with ions of 18Oxygen using a machine called the Super-Heavy Ion Linear Accelerator. 

249Ca + 18O rarrow.gif (63 bytes) 263Sg rarrow.gif (63 bytes) 259Rf rarrow.gif (63 bytes) 255No

In September 1974, a Soviet team led by G.N. Flerov at the Joint Institute for Nuclear Research at Dubna, Russia reported producing an isotope with mass number 259 and a half-life of 0.48 seconds.  Their method involved bombarding atoms of 207Pb and 208Pb with ions of 54Cr with a device called a cyclotron.

1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d10 4f14
5s2 5p6 5d10 5f14
6s2 6p6 6d4
7s2

Because their work was independently confirmed first, the Americans suggested the name seaborgium to honor the American chemist Glenn T. Seaborg credited as a member of the American team along with Ghiorso, J.M. Nitschke, J.R. Alonso, C.T. Alonso, M. Nurmia, E. Kenneth Hulet, and R.W. Lougheed in recognition of his participation in the discovery of several other actinides.  The name selected by the team became controversial.   An international committee decided in 1992 that the Berkeley and Dubna laboratories should share credit for the discovery.

seaborg.jpg (14780 bytes)

Glenn T. Seaborg

An element naming controversy erupted and as a result IUPAC adopted unnilhexium, symbol Unh) as a temporary, systematic element name.  In 1994 a committee of IUPAC recommended that element 106 be named rutherfordium and adopted a rule that no element can be named after a living person.  This ruling was fiercely objected to by the American Chemical Society.  Critics pointed out that a precedent had been set in the naming of einstenium during Albert Einstein's life.  In 1997, as part of a compromise involving elements 104 to 108, the name seaborgium for element 106 was recognized internationally.

Isotopes

There are 16 known isotopes of Seaborgium, the longest-lived of which is 271Sg which decays through alpha decay and spontaneous fission.  It has a half-life of 2.4 minutes.  The shortest-lived isotope is 258Sg which also decays through alpha decay and spontaneous fission.  It has a half-life of 2.9 ms.

Seaborgium's isotope Seaborgium-266, has a half-life of about 21 seconds.  It decays into Rutherfordium-262 through alpha decay or decays through spontaneous fission..

atom.gif (700 bytes)

Isotope  
Atomic Mass
 
Half-Life
258Sg 258.11317 2.9 ms
259Sg 259.11450 580 ms
260Sg 260.11442 3.8 ms
261Sg 261.11612 230 ms
262Sg 262.1164 8 ms
263Sg 263.11832 1.0 seconds
264Sg 264.11893 ~0.4 seconds
265Sg 265.12111 8 seconds
266Sg 266.12207 21 seconds
267Sg 267.12443 19 ms
268Sg 268.12561 ~30 seconds
269Sg 269.12876 35 seconds
270Sg 270.13033 ~10 minutes
271Sg 271.13347 2.4 minutes
272Sg 272.13516 ~1 hours
273Sg 273.13822 ~1 minutes

atom.gif (700 bytes)

Seaborgium Data
 

Atomic Structure

  • Atomic Radius:
  • Atomic Volume:
  • Covalent Radius:
  • Cross Section: (Thermal Neutron Capture) Barns: 
  • Crystal Structure:
  • Electron Configuration:
    1s2 2s2p6 3s2p6d10 4s2p6d10f14 5s2p6d10f14 6s2p6d4 7s2
  • Electrons per Energy Level: 2, 8, 18, 32, 32, 12, 2
  • Ionic Radius:
  • Filling Orbital:
  • Number of Electrons (with no charge): 106
  • Number of Neutrons (most common/stable nuclide): 157
  • Number of Protons: 106
  • Oxidation States:
  • Valence Electrons:

Chemical Properties

  • Electrochemical Equivalent:
  • Electron Work Function:
  • Electronegativity: N/A (Pauling); N/A (Allrod Rochow)
  • Heat of Fusion: kJ/mol
  • Incompatibilities:
  • Ionization Potential
    • First:
  • Valence Electron Potential (-eV):

Physical Properties

  • Atomic Mass Average: 263
  • Boiling Point:
  • Coefficient of Lineal Thermal Expansion/K-1: N/A
  • Conductivity
    Electrical:
    Thermal:
  • Description:
    Man made radioactive element that does not occur in nature.
  • Flammablity Class:
  • Freezing Point: see melting point
  • Heat of Vaporization: kJ/mol
  • Melting Point:
  • Physical State (at 20C & 1atm):
  • Specific Heat:

Regulatory / Health

  • CAS Number
    • 54038-81-2
  • NFPA 704
    • Health:
    • Fire:
    • Reactivity:
    • Special Hazard: Radioactive<
    • OSHA Permissible Exposure Limit (PEL)
      • No limits set by OSHA
    • OSHA PEL Vacated 1989
      • No limits set by OSHA
    • NIOSH Recommended Exposure Limit (REL)
      • No limits set by NIOSH
    • Levels In Humans:
      Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
      • Blood/mg dm-3: n/a
      • Bone/p.p.m: n/a
      • Liver/p.p.m: n/a
      • Muscle/p.p.m: n/a
      • Daily Dietary Intake: n/a
      • Total Mass In Avg. 70kg human: n/a

    Who / Where / When / How

    • Discoverer: Albert Ghiorso, et al workers of the Lawrence Berkeley and Livermore Laboratories
    • Discovery Location: Lawrence Berkeley Laborator
    • Discovery Year: 1974
    • Name Origin:
      Named for Glenn T. Seaborg, an American nuclear chemist and winner of a Nobel prize.
    • Abundance:
      • Earth's Crust/p.p.m.: N/A
      • Seawater/p.p.m.: nil
      • Atmosphere/p.p.m.: N/A
      • Sun (Relative to H=1E12): N/A
    • Sources:
      Synthetically produced by bombarding Cf-249 with O-18 or CM-248 with Ne-22. Very few atoms have ever been produced.
    • Uses:
      It is of research interest only.
    • Additional Notes:
      In August of 1997 the International Union of Pure and Applied Chemistry announced the official naming of this element as Seaborgium

Transition Metals
Group 3
(IIIB)
4
(IVB)
5
(VB)
6
(VIB)
7
(VIIB)
8
(VIIIB)
9
(VIIIB)
10 (VIIIB) 11
(IB)
12
(IIB)
Period 4 21
Sc
44.95
22
Ti
47.86
23
V
50.94
24
Cr
51.99
25
Mn
54.93
26
Fe
55.84
27
Co
58.93
28
Ni
58.69
29
Cu
63.54
30
Zn
65.39
Period 5 39
Y
88.90
40
Zr
91.22
41
Nb
92.90
42
Mo
95.94
43
Tc
98.00
44
Ru
101.0
45
Rh
102.9
46
Pd
106.4
47
Ag
107.8
48
Cd
112.4
Period 6 57
La
138.9
72
Hf
178.4
73
Ta
180.9
74
W
183.8
75
Re
186.2
76
Os
190.2
77
Ir
192.2
78
Pt
195.0
79
Au
196.9
80
Hg
200.5
Period 7 89
Ac
227.0
104
Rf
261.0
105
Db
262.0
106
Sg
266.0
107
Bh
264.0
108
Hs
269.0
109
Mt
268.0
110
Ds
269.0
111
Rg
272.0
112
Uub
277.0