Bohrium

Bohrium (Bh)

Radioactive transition metal. Half-life of approximately 1/500 s. Discovered by the Joint Institute for Nuclear Research at Dubna (U.S.S.R.) in 1976. Confirmed by West German physicists at the Heavy Ion Research Laboratory at Darmstadt.
Atomic Number107
Atomic Weight274
Mass Number260
Group7
Period7
Blockd
Protons107 p+
Neutrons153 n0
Electrons107 e-
Electron shell 107 Bohrium.svg Animated Bohr Model of Bh (Bohrium) Enhanced Bohr Model of Bh (Bohrium) Bohr Model: Bh (Bohrium) Orbital Diagram of Bh (Bohrium)

Properties

Atomic Radius
Molar Volume
Covalent Radius
141 pm
Metallic Radius
Ionic Radius
Crystal Radius
Van der Waals Radius
Density
37.1 g/cm³
Energy
Proton Affinity
Electron Affinity
Ionization Energy
Heat of Vaporization
Heat of Fusion
Heat of Formation
Electrons
Electron Shells2, 8, 18, 32, 32, 13, 2
Valence Electrons7
Electron Configuration[Rn] 5f14 6d5 7s2
Oxidation States7
Electronegativity
Electrophilicity
Phases
PhaseSolid
Gas Phase
Boiling Point
Melting Point
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Colorless
Appearance
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
Molar Heat Capacity
Specific Heat Capacity
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type
Electrical Conductivity
Electrical Resistivity
Superconducting Point
Magnetism
Type
Magnetic Susceptibility (Mass)
Magnetic Susceptibility (Molar)
Magnetic Susceptibility (Volume)
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal Structure ()
Lattice Constant
Lattice Angles
Mechanical Properties
Hardness
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound
Classification
CategoryTransition metals, Transition metals
CAS GroupVIIA
IUPAC GroupVIIB
Glawe Number
Mendeleev Number58
Pettifor Number
Geochemical Class
Goldschmidt Classsynthetic
Other
Gas Basicity
Dipole Polarizability
38 ± 4 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
Neutron Mass Absorption
Quantum Numbers6S5/2
Space Group ()

Isotopes of Bohrium

Stable Isotopes0
Unstable Isotopes19
Radioactive Isotopes19

260Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
260.121443 ± 0.000211 Da
Mass Number260
G-Factor
Half Life
41 ± 14 ms
Spin
Quadrupole Moment
Discovery Year2008
Parity

260Bh Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%
SF (spontaneous fission)%

261Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
261.121395733 ± 0.000193026 Da
Mass Number261
G-Factor
Half Life
12.8 ± 3.2 ms
Spin5/2
Quadrupole Moment
Discovery Year1989
Parity-

261Bh Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)%

262Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
262.122654688 ± 0.000099919 Da
Mass Number262
G-Factor
Half Life
84 ± 11 ms
Spin
Quadrupole Moment
Discovery Year1981
Parity

262Bh Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)20%

263Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
263.122916 ± 0.000328 Da
Mass Number263
G-Factor
Half Life
Spin5/2
Quadrupole Moment
Discovery Year
Parity-

263Bh Decay Modes
Decay ModeIntensity
α (α emission)%

264Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
264.124486 ± 0.00019 Da
Mass Number264
G-Factor
Half Life
1.07 ± 0.21 s
Spin
Quadrupole Moment
Discovery Year1995
Parity

264Bh Decay Modes
Decay ModeIntensity
α (α emission)86%
SF (spontaneous fission)14%
β+ (β+ decay; β+ = ϵ + e+)%

265Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
265.124955 ± 0.000257 Da
Mass Number265
G-Factor
Half Life
1.19 ± 0.52 s
Spin5/2
Quadrupole Moment
Discovery Year2004
Parity-

265Bh Decay Modes
Decay ModeIntensity
α (α emission)%

266Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
266.12679 ± 0.000175 Da
Mass Number266
G-Factor
Half Life
10.6 ± 2.2 s
Spin
Quadrupole Moment
Discovery Year2000
Parity

266Bh Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%
SF (spontaneous fission)%

267Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
267.127499 ± 0.000282 Da
Mass Number267
G-Factor
Half Life
22 ± 10 s
Spin5/2
Quadrupole Moment
Discovery Year2000
Parity-

267Bh Decay Modes
Decay ModeIntensity
α (α emission)100%

268Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
268.129584 ± 0.00041 Da
Mass Number268
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

268Bh Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

269Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
269.130411 ± 0.000402 Da
Mass Number269
G-Factor
Half Life
Spin5/2
Quadrupole Moment
Discovery Year
Parity-

269Bh Decay Modes
Decay ModeIntensity
α (α emission)%

270Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
270.133366 ± 0.00032 Da
Mass Number270
G-Factor
Half Life
3.8 ± 3 m
Spin
Quadrupole Moment
Discovery Year2007
Parity

270Bh Decay Modes
Decay ModeIntensity
α (α emission)100%

271Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
271.135115 ± 0.000412 Da
Mass Number271
G-Factor
Half Life
2.9 ± 1.9 s
Spin
Quadrupole Moment
Discovery Year2013
Parity

271Bh Decay Modes
Decay ModeIntensity
α (α emission)100%

272Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
272.138259 ± 0.000571 Da
Mass Number272
G-Factor
Half Life
11.3 ± 1.8 s
Spin
Quadrupole Moment
Discovery Year2004
Parity

272Bh Decay Modes
Decay ModeIntensity
α (α emission)100%

273Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
273.140294 ± 0.000703 Da
Mass Number273
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

273Bh Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

274Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
274.143599 ± 0.00062 Da
Mass Number274
G-Factor
Half Life
57 ± 27 s
Spin
Quadrupole Moment
Discovery Year2010
Parity

274Bh Decay Modes
Decay ModeIntensity
α (α emission)100%

275Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
275.145766 ± 0.000644 Da
Mass Number275
G-Factor
Half Life
Spin5/2
Quadrupole Moment
Discovery Year
Parity-

275Bh Decay Modes
Decay ModeIntensity
SF (spontaneous fission)%

276Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
276.149169 ± 0.000644 Da
Mass Number276
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

276Bh Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

277Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
277.151477 ± 0.000644 Da
Mass Number277
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

277Bh Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

278Bh

AbundanceRadioactive ☢️
Relative Atomic Mass
278.154988 ± 0.000429 Da
Mass Number278
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year2016
Parity

278Bh Decay Modes
Decay ModeIntensity
SF (spontaneous fission)100%
α (α emission)%

History

Bohrium was first convincingly synthesized in 1981 by a German research team led by Peter Armbruster and Gottfried Münzenberg at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung) in Darmstadt. The team bombarded a target of bismuth-209 with accelerated nuclei of chromium-54 to produce 5 atoms of the isotope bohrium-262. Named after Niels Bohr, the Danish physicist

DiscoverersHeavy Ion Research Laboratory (HIRL)
Discovery LocationGermany
Discovery Year1976
Etymology (Name Origin)Named in honor of Niels Bohr
Pronunciationneels-BOR-i-em (English)
Bohrium is harmful due to its radioactivity
The only confirmed example of isomerism in bohrium is in the isotope 262Bh

Uses

Bohrium is used for scientific research purposes only. It has no significant commercial applications.

Sources

Obtained by bombarding bismuth-204 with chromium-54.

Abundance
Abundance in Earth's crust
Abundance in Oceans
Abundance in Human Body
0 %
Abundance in Meteor
0 %
Abundance in Sun
0 %
Abundance in Universe
0 %

Nuclear Screening Constants