Boron (B)
metalloidSolid
Standard Atomic Weight
10.81 u [10.806, 10.821]Electron configuration
[He] 2s2 2p1Melting point
2074.85 °CBoiling point
3999.85 °CDensity
2370 kg/m³Oxidation states
−5, −1, 0, +1, +2, +3Electronegativity (Pauling)
2.04Ionization energy (1st)
8.298019 eVDiscovery year
1808Atomic radius
85 pmDetails
Boron is a light metalloid in group 13, notable for electron-deficient bonding and a rich cluster chemistry. It occurs naturally only in compounds, mainly as borates in evaporite minerals and brines. Elemental boron is difficult to prepare in high purity and has several allotropes built from B₁₂ icosahedra. Technologically, boron is most important through borate minerals, borosilicate glass, detergents, ceramics, fertilizers, and neutron-absorbing materials.
An element of group 13 of the periodic table. There are two allotropes, amorphous boron is a brown power, but metallic boron is black. The metallic form is hard (9.3 on Mohs' scale) and a bad conductor in room temperatures. It is never found free in nature. Boron-10 is used in nuclear reactor control rods and shields. It was discovered in 1808 by Sir Humphry Davy and by J.L. Gay-Lussac and L.J. Thenard.
The name derives from the Arabic buraq for "white". Although its compounds were known for thousands of years, it was not isolated until 1808 by the French chemists Louis-Joseph Gay-Lussac and Louis-Jacques Thenard.
Boron was discovered by Joseph-Louis Gay-Lussac and Louis-Jaques Thénard, French chemists, and independently by Sir Humphry Davy, an English chemist, in 1808. They all isolated boron by combining boric acid (H3BO3) with potassium. Today, boron is obtained by heating borax (Na2B4O7·10H2O) with carbon, although other methods are used if high-purity boron is required.
From the Arabic word Buraq, Persian Burah. Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard.
Pure boron is usually encountered as a dark brown to black, hard, brittle solid with a semiconducting character. Amorphous boron is a powder, while crystalline allotropes have a dark, lustrous appearance; their properties depend strongly on purity and structure.
Most boron use is in compounds rather than the free element. Borates are used in glass fiber insulation, borosilicate glass, enamels, ceramics, detergents, flame retardants, and micronutrient fertilizers. Boron carbide, B₄C, is used in armor, abrasives, and control rods because it is very hard and absorbs neutrons. Elemental boron is used in small amounts in specialty alloys, pyrotechnic compositions, and semiconductor work. The isotope ¹⁰B is important in neutron detection, reactor control, and boron neutron capture therapy research and applications.
Boron is used in pyrotechnics and flares to produce a green color. Boron has also been used in some rockets as an ignition source. Boron-10, one of the naturally occurring isotopes of boron, is a good absorber of neutrons and is used in the control rods of nuclear reactors, as a radiation shield and as a neutron detector. Boron filaments are used in the aerospace industry because of their high-strength and lightweight.
Boron forms several commercially important compounds. The most important boron compound is sodium borate pentahydrate (Na2B4O7·5H2O). Large amounts of this compound are used in the manufacture of fiberglass insulation and sodium perborate bleach. The second most important compound is boric acid (H3BO3), which is used to manufacture textile fiberglass and is used in cellulose insulation as a flame retardant. Sodium borate decahydrate (Na2B4O7·10H2O), better known as borax, is the third most important boron compound. Borax is used in laundry products and as a mild antiseptic. Borax is also a key ingredient in a substance known as Oobleck, a strange material 6th grade students experiment with while participating in Jefferson Lab's BEAMS program. Other boron compounds are used to make borosilicate glasses, enamels for covering steel and as a potential medicine for treating arthritis.
Amorphous boron is used in pyrotechnic flares to provide a distinctive green color, and in rockets as an igniter.
By far the most commercially important boron compound in terms of dollar sales is Na2B4O7 • 5H2O. This pentahydrate is used in very large quantities in the manufacture of insulation fiberglass and sodium perborate bleach.
Boric acid is also an important boron compound with major markets in textile products. Use of borax as a mild antiseptic is minor in economical terms. Boron compounds are also extensively used in the manufacture of borosilicate glasses. Other boron compounds show promise in treating arthritis.
The isotope boron-10 is used as a control for nuclear reactors, as a shield for nuclear radiation, and in instruments used for detecting neutrons. Boron nitride has remarkable properties and can be used to make a material as hard as diamond. The nitride also behaves like an electrical insulator but conducts heat like a metal.
Boron also has lubricating properties similar to graphite. The hydrides are easily oxidized with considerable energy liberation, and have been studied for use as rocket fuels. Demand is increasing for boron filaments, a high-strength, lightweight material chiefly employed for advanced aerospace structures.
Boron is similar to carbon in that it has a capacity to form stable covalently bonded molecular networks. Carbonates, metalloboranes, phosphacarboranes, and other families comprise thousands of compounds.
Isotopes in Earth/Planetary Science
Molecules, atoms, and ions of the stable isotopes of boron possess slightly different physical and chemical properties, and they commonly will be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. Natural terrestrial materials show a substantial variation in boron isotopic abundance (Fig. IUPAC.5.1). The relative abundances of 10B and 11B have been used in a variety of environmental tracer applications [51] A. Vengosh, K. G. Heumann, S. Jaraske, R. Kasher. Environ. Sci. Technol.28, 1968 (1994)., [52] A. Vengosh. Biol. Trace Elem. Res.66, 145 (1998).. The isotope-amount ratio n(11B)/n(10B) of boron in a water sample depends on the source of the water and region through which the water flows, and it may also be affected by some types of contamination, such as dissolved borate in domestic wastewater. Different water sources may have their own distinct boron isotopic composition, e.g. seawater versus water from continental sources (Fig. IUPAC.5.1).
Isotopes in Industry
The large value of the absorption cross section of 10B for thermal neutrons makes this isotope useful for counting neutrons. 10B is being studied as a potential replacement for 3He in radiation detectors [32] G. V. Jean. Advancing Hidden Nuclear Material Detection, National Defense Industrial Association (2014), Feb. 28; http://www.nationaldefensemagazine.org/archive/2010/December/Pages/AdvancingHiddenNuclearMaterialDetection.aspx., [53] L. Foulke. Director of Nuclear Education Outreach, University of Pittsburgh. Introduction to Reactivity and Reactor Control, IAEA Workshop on Desktop Simulation (2014), Feb. 22; http://www.iaea.org/NuclearPower/Downloadable/Meetings/2011/2011-10-03-10-14-WS-NPTD/Foulke.1-Introduction.Reactivity.pdf., [54] P. Frame. Boron Trifluoride (BF3) Neutron Detectors, Oak Ridge Associated Universities (2014), Feb. 22; http://www.orau.org/PTP/collection/proportional%20counters/bf3info.htm.. The large thermal absorption cross section of 10B makes the isotope useful in control rods (Fig. IUPAC.5.2) [55] United States Nuclear Regulatory Commission. Pressurized Water Reactors, U.S. Nuclear Regulatory Commission (2014), Feb. 22; http://www.nrc.gov/reactors/pwrs.html..
Isotopes in Medicine
10B has a high thermal neutron absorption cross section and can readily absorb neutrons via the reaction 10B+n→ 7Li+α. The alpha particles resulting from this reaction carry away a relatively large kinetic energy and are useful for the treatment of malignant tumors in cancer patients [56] D. Gabel. Radiother Oncol.30, 199 (1994)., [57] D. N. Slatkin. Neutron News1, 25 (1990)., [58] R. F. Barth, J. A. Coderre, M. C. G. Vicente, T. E. Blue. Clin. Cancer Res.11, 3987 (2005)..
Boron commonly shows the +3 oxidation state, but its bonding is often better described by electron-deficient multicenter structures. Boric acid, H₃BO₃, is a weak Lewis acid in water and a precursor to many borates. Borax, Na₂B₄O₇·10H₂O, is a major industrial borate. Boron trioxide, B₂O₃, is a glass-forming oxide. Boron trifluoride, BF₃, is a strong Lewis acid used in synthesis, while diborane, B₂H₆, illustrates boron hydride cluster chemistry. Boron nitride, BN, occurs in graphite-like and diamond-like forms with useful thermal and mechanical properties.
See more information at the Boron compound page.
Elemental boron is not highly toxic in compact form, but fine powders can irritate eyes, skin, and the respiratory tract and may be combustible under some conditions. Soluble borates and boric acid, H₃BO₃, can be harmful at sufficient dose, especially with repeated or high exposure. Boron trifluoride, BF₃, and diborane, B₂H₆, are far more hazardous: the former is corrosive and toxic, and the latter is toxic and flammable. Neutron-absorbing ¹⁰B is stable and is not itself radioactive.
Elemental boron and the borates are not considered to be toxic, and they do not require special care in handling. However, some of the more exotic boron hydrogen compounds are definitely toxic and do require care.
Boron is a natural trace element in rocks, soils, seawater, geothermal waters, and evaporite deposits. Weathering releases borate species that are mobile in water, especially under neutral to alkaline conditions. It is an essential micronutrient for higher plants, but the margin between deficiency and toxicity can be narrow in sensitive crops. Natural and industrial sources include volcanic emissions, seawater aerosols, mining, glass manufacture, detergents, and irrigation return flows.
Boron is supplied almost entirely from borate minerals and boron-rich brines, not from mining elemental boron. Major commercial materials include borax, kernite, ulexite, and colemanite, which are refined into boric acid, H₃BO₃, borax, Na₂B₄O₇·10H₂O, and other borates. Demand is led by glass, fiberglass, ceramics, detergents, agriculture, and specialty chemical uses. High-purity elemental boron and isotopically enriched ¹⁰B are much smaller specialty markets, with enrichment adding significant cost. Recycling is limited because boron is often dispersed in glass, ceramics, or formulations.
The element is not found free in nature, but occurs as orthoboric acid usually found in certain volcanic spring waters and as borates in boron and colemantie.
Important sources of boron are ore rasorite (kernite) and tincal (borax ore). Both of these ores are found in the Mojave Desert. Tincal is the most important source of boron from the Mojave. Extensive borax deposits are also found in Turkey.
Boron exists naturally as 19.78% 10B isotope and 80.22% 11B isotope. High-purity crystalline boron may be prepared by the vapor phase reduction of boron trichloride or tribromide with hydrogen on electrically heated filaments. The impure or amorphous, boron, a brownish-black powder, can be obtained by heating the trioxide with magnesium powder.
Boron of 99.9999% purity has been produced and is available commercially. Elemental boron has an energy band gap of 1.50 to 1.56 eV, which is higher than that of either silicon or germanium.
Boron is rare in the universe compared with neighboring light elements. It is not made efficiently by ordinary stellar fusion and is readily destroyed at stellar interior temperatures. Most cosmic boron is attributed to spallation reactions in which cosmic rays fragment heavier nuclei such as carbon, nitrogen, and oxygen. In the Solar System it is concentrated mainly in crustal and evaporitic materials rather than metallic or volatile reservoirs.
- Natural boron is mainly a mixture of ¹⁰B and ¹¹B.
- The large neutron-capture cross section of ¹⁰B gives boron unusual nuclear importance for a light element.
- Many crystalline boron structures are based on B₁₂ icosahedra rather than simple close packing.
- Boron deficiency and boron toxicity can both occur in agriculture.
- Borosilicate glass resists thermal shock partly because boron lowers thermal expansion.
- Boron carbide, B₄C, is one of the hardest widely used ceramic materials.
Images
Properties
Physical
- Atomic radius (empirical)
- 85 pm Compare Atomic radius (empirical) of all elements →
- Covalent radius
- 84 pm Compare Covalent radius of all elements →
- Van der Waals radius
- 192 pm Compare Van der Waals radius of all elements →
- Metallic radius
- 80 pm Compare Metallic radius of all elements →
- Density
- 2370 kg/m³ Compare Density of all elements →
- Molar volume
- 0.0046 L/mol
- Phase at STP
- Solid Compare Phase at STP of all elements →
- Melting point
- 2074.85 °C Compare Melting point of all elements →
- Boiling point
- 3999.85 °C Compare Boiling point of all elements →
- Thermal conductivity
- 27.4 W/(m·K) Compare Thermal conductivity of all elements →
- Specific heat capacity
- 1.026 J/(g·K) Compare Specific heat capacity of all elements →
- Molar heat capacity
- 11.087 J/(mol·K) Compare Molar heat capacity of all elements →
- Crystal structure
- Tetragonal Compare Crystal structure of all elements →
Chemical
- Electronegativity (Pauling)
- 2.04 Compare Electronegativity (Pauling) of all elements →
- Electronegativity (Allen)
- 2.051
- Electron affinity
- 0.27972 eV
- Ionization energy (1st)
- 8.298019 eV Compare Ionization energy (1st) of all elements →
- Ionization energy (2nd)
- 25.154917 eV Compare Ionization energy (2nd) of all elements →
- Ionization energy (3rd)
- 37.930721 eV Compare Ionization energy (3rd) of all elements →
- Ionization energy (4th)
- 259.375272 eV Compare Ionization energy (4th) of all elements →
- Ionization energy (5th)
- 340.227194 eV Compare Ionization energy (5th) of all elements →
- Oxidation states
- −5, −1, 0, +1, +2, +3 Compare Oxidation states of all elements →
- Valence electrons
- 3 Compare Valence electrons of all elements →
- Electron configuration
- [He] 2s2 2p1
Thermodynamic
- Heat of fusion
- 0.52028813 eV Compare Heat of fusion of all elements →
- Heat of vaporization
- 4.974867 eV Compare Heat of vaporization of all elements →
- Heat of sublimation
- 5.855833 eV
- Heat of atomization
- 5.855833 eV
- Atomization enthalpy
- 5.855833 eV
Nuclear
- Protons
- 5 Compare Protons of all elements →
- Neutrons
- 6 Compare Neutrons of all elements →
- Known isotopes
- 16 Compare Known isotopes of all elements →
- Stable isotopes
- 2 Compare Stable isotopes of all elements →
- Most stable isotope
- B-11
- Discovery year
- 1808
Abundance
- Abundance (Earth's crust)
- 10 mg/kg Compare Abundance (Earth's crust) of all elements →
- Abundance (ocean)
- 4.44 mg/L Compare Abundance (ocean) of all elements →
Crystal Structure
- Lattice constant a
- 873 pm
Electronic Structure
- Electrons per shell
- 2, 3 Compare Electrons per shell of all elements →
Identifiers
- CAS number
- 7440-42-8 Compare CAS number of all elements →
- Term symbol
- 2P°1/2
- InChI
- InChI=1S/B
- InChI Key
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N
Electron Configuration Measured
B: 2s² 2p¹[He] 2s² 2p¹1s² 2s² 2p¹Atomic model
Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.
Schematic atomic model, not to scale.
Atomic Fingerprint
Emission / Absorption Spectrum
Isotope Distribution
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|---|---|---|
| 10 Stable | 10.01293695 ± 0.00000041 | 19.9000% | Stable |
| 11 Stable | 11.00930536 ± 0.00000045 | 80.1000% | Stable |
Phase / State
Reason: 2049.8 °C below melting point (2074.85 °C)
Schematic, not to scale
Phase transition points
Transition energies
Energy required to melt 1 mol at melting point
Energy required to vaporize 1 mol at boiling point
Energy required to sublime 1 mol at sublimation point
Density
At standard conditions
At standard conditions
Atomic Spectra
Lines Holdings ?
| Ion | Charge | Total lines | Transition probabilities | Level designations |
|---|---|---|---|---|
| B I | 0 | 371 | 269 | 371 |
| 11B I Isotope | 0 | 53 | 0 | 53 |
| 10B I Isotope | 0 | 11 | 0 | 11 |
| B II | +1 | 592 | 435 | 592 |
| 10B II Isotope | +1 | 9 | 0 | 9 |
| 11B II Isotope | +1 | 9 | 0 | 9 |
| B III | +2 | 390 | 106 | 390 |
| B IV | +3 | 478 | 234 | 478 |
| B V | +4 | 258 | 240 | 258 |
Levels Holdings ?
| Ion | Charge | Levels |
|---|---|---|
| B I | 0 | 125 |
| 11B I Isotope | 0 | 69 |
| 10B I Isotope | 0 | 29 |
| B II | +1 | 157 |
| 10B II Isotope | +1 | 10 |
| 11B II Isotope | +1 | 10 |
| B III | +2 | 150 |
| B IV | +3 | 174 |
| B V | +4 | 101 |
Ionic Radii
| Charge | Coordination | Spin | Radius |
|---|---|---|---|
| +3 | 3 | N/A | 1 pm |
| +3 | 4 | N/A | 11 pm |
| +3 | 6 | N/A | 27 pm |
Compounds
Isotopes (2)
| Mass number | Atomic mass (u) | Natural abundance | Half-life | Decay mode | |
|---|---|---|---|---|---|
| 10 Stable | 10.01293695 ± 0.00000041 | 19.9000% ± 0.7000% | Stable | stable | |
| 11 Stable | 11.00930536 ± 0.00000045 | 80.1000% ± 0.7000% | Stable | stable |
Spectral Lines
| Wavelength (nm) | Intensity | Ion stage | Type | Transition | Accuracy | Source | |
|---|---|---|---|---|---|---|---|
| 391.482 nm | N/A | B II | emission | 1s2.2s.2p 1P* → 1s2.2p2 3P | Measured | NIST | |
| 391.687 nm | N/A | B II | emission | 1s2.2s.2p 1P* → 1s2.2p2 3P | Measured | NIST | |
| 391.817 nm | N/A | B II | emission | 1s2.2s.2p 1P* → 1s2.2p2 3P | Measured | NIST | |
| 394.447 nm | N/A | B II | emission | 1s2.2p.3d 3F* → 1s2.2p.4f 3F | Measured | NIST | |
| 394.587 nm | N/A | B II | emission | 1s2.2p.3d 3F* → 1s2.2p.4f 3F | Measured | NIST | |
| 394.82 nm | N/A | B II | emission | 1s2.2p.3d 3F* → 1s2.2p.4f 3F | Measured | NIST | |
| 395.038 nm | 18 | B II | emission | 1s2.2p.3d 1D* → 1s2.2p.4f 1F | Measured | NIST | |
| 395.1698 nm | N/A | B II | emission | 1s2.2p2 1D → 1s2.2p2 1S | Measured | NIST | |
| 399.024 nm | 70 | B II | emission | 1s2.2s.4p 1P* → 1s2.2s.8d 1D | Measured | NIST | |
| 400.017 nm | 136 | B III | emission | 1s.2s.(3S).4d 4D → 1s.2s.(3S).5f 4F* | Measured | NIST | |
| 412.1928 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4f 3F* | Measured | NIST | |
| 412.1928 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4f 3F* | Measured | NIST | |
| 412.1928 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4f 3F* | Measured | NIST | |
| 412.1928 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4f 3F* | Measured | NIST | |
| 412.1928 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4f 3F* | Measured | NIST | |
| 412.1928 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4f 3F* | Measured | NIST | |
| 414.697 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.8f 2F* | Measured | NIST | |
| 414.708 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.8f 2F* | Measured | NIST | |
| 414.708 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.8f 2F* | Measured | NIST | |
| 415.284 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 415.284 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 415.471 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 415.471 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 415.471 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 415.584 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 417.896 nm | N/A | B I | emission | 2s2.3p 2P* → 2s.2p2 2P | Measured | NIST | |
| 417.927 nm | N/A | B I | emission | 2s2.3p 2P* → 2s.2p2 2P | Measured | NIST | |
| 418.099 nm | N/A | B I | emission | 2s2.3p 2P* → 2s.2p2 2P | Measured | NIST | |
| 418.13 nm | N/A | B I | emission | 2s2.3p 2P* → 2s.2p2 2P | Measured | NIST | |
| 419.4792 nm | 180 | B II | emission | 1s2.2s.3p 1P* → 1s2.2s.4s 1S | Measured | NIST | |
| 419.773 nm | 30 | B IV | emission | 1s.5s 3S → 1s.6p 3P* | Measured | NIST | |
| 424.3 nm | 300 | B III | emission | 1s2.4p 2P* → 1s2.5d 2D | Measured | NIST | |
| 424.359 nm | N/A | B III | emission | 1s2.4p 2P* → 1s2.5d 2D | Measured | NIST | |
| 424.37 nm | N/A | B III | emission | 1s2.4p 2P* → 1s2.5d 2D | Measured | NIST | |
| 427.274 nm | 50 | B II | emission | 1s2.2s.4s 3S → 1s2.2s.6p 3P* | Measured | NIST | |
| 429.571 nm | 50 | B II | emission | 1s2.2s.4p 1P* → 1s2.2s.7d 1D | Measured | NIST | |
| 436.147 nm | 60 | B III | emission | 1s.2p.(3P*).4f 2F → 1s.2p.(3P*).5g 2G* | Measured | NIST | |
| 436.61 nm | 100 | B III | emission | 1s.2p.(3P*).4f 4F → 1s.2p.(3P*).5g 4G* | Measured | NIST | |
| 443.11 nm | N/A | B II | emission | 1s2.2p.3d 3D* → 1s2.2p.4f 3F | Measured | NIST | |
| 443.185 nm | N/A | B II | emission | 1s2.2p.3d 3D* → 1s2.2p.4f 3F | Measured | NIST | |
| 443.291 nm | N/A | B II | emission | 1s2.2p.3d 3D* → 1s2.2p.4f 3F | Measured | NIST | |
| 445.943 nm | N/A | B IV | emission | 1s.5p 3P* → 1s.6d 3D | Measured | NIST | |
| 445.943 nm | N/A | B IV | emission | 1s.5p 3P* → 1s.6d 3D | Measured | NIST | |
| 445.943 nm | N/A | B IV | emission | 1s.5p 3P* → 1s.6d 3D | Measured | NIST | |
| 447.112 nm | N/A | B III | emission | 1s2.5s 2S → 1s2.7p 2P* | Measured | NIST | |
| 447.112 nm | N/A | B III | emission | 1s2.5s 2S → 1s2.7p 2P* | Measured | NIST | |
| 447.2029 nm | N/A | B II | emission | 1s2.2s.3p 3P* → 1s2.2s.4s 3S | Measured | NIST | |
| 447.2151 nm | N/A | B II | emission | 1s2.2s.3p 3P* → 1s2.2s.4s 3S | Measured | NIST | |
| 447.2862 nm | 470 | B II | emission | 1s2.2s.3p 3P* → 1s2.2s.4s 3S | Measured | NIST | |
| 448.692 nm | N/A | B III | emission | 1s2.4d 2D → 1s2.5f 2F* | Measured | NIST | |
| 448.71 nm | N/A | B III | emission | 1s2.4d 2D → 1s2.5f 2F* | Measured | NIST | |
| 449.09 nm | 20 | B IV | emission | 1s.2s 1S → 1s.2p 1P* | Measured | NIST | |
| 449.773 nm | 1700 | B III | emission | 1s2.4f 2F* → 1s2.5g 2G | Measured | NIST | |
| 449.853 nm | N/A | B III | emission | 1s2.4f 2F* → 1s2.5f 2F* | Measured | NIST | |
| 449.859 nm | N/A | B III | emission | 1s2.4f 2F* → 1s2.5f 2F* | Measured | NIST | |
| 450.481 nm | N/A | B III | emission | 1s2.4f 2F* → 1s2.5d 2D | Measured | NIST | |
| 450.482 nm | N/A | B III | emission | 1s2.4f 2F* → 1s2.5d 2D | Measured | NIST | |
| 451.9912773 nm | N/A | B V | emission | 7i 2I → 9k 2K* | Measured | NIST | |
| 451.9946377 nm | N/A | B V | emission | 7i 2I → 9k 2K* | Measured | NIST | |
| 453.229 nm | N/A | B II | emission | 1s2.2s.4f 1F* → 1s2.2p.3p 1D | Measured | NIST | |
| 459.72 nm | N/A | B III | emission | 1s.2s.(3S).4d 4D → 1s.2s.(3S).5p 4P* | Measured | NIST | |
| 459.73 nm | N/A | B III | emission | 1s.2p.(3P*).4p 4P → 1s.2p.(3P*).5s 4P* | Measured | NIST | |
| 461.114 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3S | Measured | NIST | |
| 461.114 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3S | Measured | NIST | |
| 461.114 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2p.3p 3S | Measured | NIST | |
| 461.32 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6p 1P* | Measured | NIST | |
| 463.217 nm | N/A | B III | emission | 1s2.4d 2D → 1s2.5p 2P* | Measured | NIST | |
| 463.243 nm | N/A | B III | emission | 1s2.4d 2D → 1s2.5p 2P* | Measured | NIST | |
| 463.263 nm | N/A | B III | emission | 1s2.4d 2D → 1s2.5p 2P* | Measured | NIST | |
| 464.69 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 1F* | Measured | NIST | |
| 464.69 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 1F* | Measured | NIST | |
| 464.701 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 3F* | Measured | NIST | |
| 464.701 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 3F* | Measured | NIST | |
| 464.701 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 3F* | Measured | NIST | |
| 464.701 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 3F* | Measured | NIST | |
| 464.701 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 3F* | Measured | NIST | |
| 464.701 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6f 3F* | Measured | NIST | |
| 465.58 nm | N/A | B IV | emission | 1s.5d 1D → 1s.6f 1F* | Measured | NIST | |
| 465.786 nm | N/A | B IV | emission | 1s.5f 3F* → 1s.6g 3G | Measured | NIST | |
| 465.786 nm | N/A | B IV | emission | 1s.5f 3F* → 1s.6g 3G | Measured | NIST | |
| 465.786 nm | N/A | B IV | emission | 1s.5f 3F* → 1s.6g 3G | Measured | NIST | |
| 465.8 nm | N/A | B IV | emission | 1s.5f 1F* → 1s.6g 3G | Measured | NIST | |
| 465.815 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6h 3H* | Measured | NIST | |
| 465.815 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6h 3H* | Measured | NIST | |
| 465.815 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6h 3H* | Measured | NIST | |
| 465.815 nm | N/A | B IV | emission | 1s.5g 1G → 1s.6h 3H* | Measured | NIST | |
| 465.92 nm | N/A | B IV | emission | 1s.5g 1G → 1s.6f 1F* | Measured | NIST | |
| 465.92 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6f 1F* | Measured | NIST | |
| 465.92 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6f 1F* | Measured | NIST | |
| 465.927 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6f 3F* | Measured | NIST | |
| 465.927 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6f 3F* | Measured | NIST | |
| 465.927 nm | N/A | B IV | emission | 1s.5g 3G → 1s.6f 3F* | Measured | NIST | |
| 465.927 nm | N/A | B IV | emission | 1s.5g 1G → 1s.6f 3F* | Measured | NIST | |
| 468.31 nm | N/A | B IV | emission | 1s.5p 1P* → 1s.6p 1P* | Measured | NIST | |
| 468.481 nm | N/A | B IV | emission | 1s.6g 3G → 1s.8h 3H* | Measured | NIST | |
| 468.489 nm | N/A | B IV | emission | 1s.6f 3F* → 1s.8g 3G | Measured | NIST | |
| 468.489 nm | N/A | B IV | emission | 1s.6f 3F* → 1s.8g 3G | Measured | NIST | |
| 468.489 nm | N/A | B IV | emission | 1s.6f 3F* → 1s.8g 3G | Measured | NIST | |
| 468.5 nm | N/A | B IV | emission | 1s.6h 3H* → 1s.8i 3I | Measured | NIST | |
| 471.612 nm | 15 | B II | emission | 1s2.2p.3d 1D* → 1s2.2p.4p 1P | Measured | NIST | |
| 471.99 nm | N/A | B IV | emission | 1s.5p 1P* → 1s.6d 1D | Measured | NIST | |
| 477.384 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6p 3P* | Measured | NIST | |
| 477.384 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6p 3P* | Measured | NIST | |
| 477.384 nm | N/A | B IV | emission | 1s.5d 3D → 1s.6p 3P* | Measured | NIST | |
| 478.42 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4p 3P* | Measured | NIST | |
| 478.42 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4p 3P* | Measured | NIST | |
| 478.4203 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4p 3P* | Measured | NIST | |
| 478.4203 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4p 3P* | Measured | NIST | |
| 478.4203 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4p 3P* | Measured | NIST | |
| 478.4203 nm | N/A | B II | emission | 1s2.2s.3d 3D → 1s2.2s.4p 3P* | Measured | NIST | |
| 481.276 nm | N/A | B IV | emission | 1s.5p 3P* → 1s.6s 3S | Measured | NIST | |
| 481.276 nm | N/A | B IV | emission | 1s.5p 3P* → 1s.6s 3S | Measured | NIST | |
| 481.276 nm | N/A | B IV | emission | 1s.5p 3P* → 1s.6s 3S | Measured | NIST | |
| 491.746 nm | 500 | B III | emission | 1s2.4p 2P* → 1s2.5s 2S | Measured | NIST | |
| 491.84 nm | 500 | B III | emission | 1s2.4p 2P* → 1s2.5s 2S | Measured | NIST | |
| 494.0365 nm | 440 | B II | emission | 1s2.2s.3d 1D → 1s2.2s.4f 1F* | Measured | NIST | |
| 494.4788284 nm | N/A | B V | emission | 6h 2H* → 7i 2I | Measured | NIST | |
| 494.4864305 nm | N/A | B V | emission | 6h 2H* → 7i 2I | Measured | NIST | |
| 498.848 nm | N/A | B III | emission | 1s2.5p 2P* → 1s2.7d 2D | Measured | NIST | |
| 498.901 nm | N/A | B III | emission | 1s2.5p 2P* → 1s2.7d 2D | Measured | NIST | |
| 512.579 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.7f 3F* | Measured | NIST | |
| 512.579 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.7f 3F* | Measured | NIST | |
| 512.579 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.7f 3F* | Measured | NIST | |
| 515.776 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.7f 2F* | Measured | NIST | |
| 515.793 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.7f 2F* | Measured | NIST | |
| 516.57 nm | N/A | B III | emission | 1s2.5f 2F* → 1s2.7g 2G | Measured | NIST | |
| 516.579 nm | N/A | B III | emission | 1s2.5f 2F* → 1s2.7g 2G | Measured | NIST | |
| 522.65 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.7p 2P* | Measured | NIST | |
| 522.65 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.7p 2P* | Measured | NIST | |
| 522.667 nm | N/A | B III | emission | 1s2.5d 2D → 1s2.7p 2P* | Measured | NIST | |
| 526.311 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2s.7g 3G | Measured | NIST | |
| 526.311 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2s.7g 3G | Measured | NIST | |
| 526.311 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2s.7g 3G | Measured | NIST | |
| 529.28 nm | N/A | B III | emission | 1s2.5p 2P* → 1s2.7s 2S | Measured | NIST | |
| 529.34 nm | N/A | B III | emission | 1s2.5p 2P* → 1s2.7s 2S | Measured | NIST | |
| 534.765 nm | 15 | B II | emission | 1s2.2s.4s 1S → 1s2.2p.3s 1P* | Measured | NIST | |
| 539.322 nm | 30 | B II | emission | 1s2.2s.4p 1P* → 1s2.2p.3p 1P | Measured | NIST | |
| 550.4527 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.11f 2F* | Measured | NIST | |
| 550.4622 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.11f 2F* | Measured | NIST | |
| 556.3146 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.10f 2F* | Measured | NIST | |
| 556.3244 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.10f 2F* | Measured | NIST | |
| 563.30717 nm | N/A | B I | emission | 2s2.3s 2S → 2s2.4p 2P* | Measured | NIST | |
| 563.32732 nm | N/A | B I | emission | 2s2.3s 2S → 2s2.4p 2P* | Measured | NIST | |
| 564.4278 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.9f 2F* | Measured | NIST | |
| 564.4379 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.9f 2F* | Measured | NIST | |
| 576.1901 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.8f 2F* | Measured | NIST | |
| 576.1901 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.8f 2F* | Measured | NIST | |
| 576.2006 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.8f 2F* | Measured | NIST | |
| 578.747 nm | N/A | B II | emission | 1s2.2s.4s 3S → 1s2.2s.5p 3P* | Measured | NIST | |
| 578.747 nm | N/A | B II | emission | 1s2.2s.4s 3S → 1s2.2s.5p 3P* | Measured | NIST | |
| 578.747 nm | N/A | B II | emission | 1s2.2s.4s 3S → 1s2.2s.5p 3P* | Measured | NIST | |
| 581.833 nm | 60 | B I | emission | 2s.2p2 2P → 2s.2p.(3P*).3d 2D* | Measured | NIST | |
| 582.116 nm | 100 | B I | emission | 2s.2p2 2P → 2s.2p.(3P*).3d 2D* | Measured | NIST | |
| 582.228 nm | 10 | B I | emission | 2s.2p2 2P → 2s.2p.(3P*).3d 2D* | Measured | NIST | |
| 594.2619 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.7f 2F* | Measured | NIST | |
| 594.2619 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.7f 2F* | Measured | NIST | |
| 594.2731 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.7f 2F* | Measured | NIST | |
| 601.35 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2s.6s 3S | Measured | NIST | |
| 601.35 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2s.6s 3S | Measured | NIST | |
| 601.35 nm | N/A | B II | emission | 1s2.2s.4p 3P* → 1s2.2s.6s 3S | Measured | NIST | |
| 602.772 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.8d 2D | Measured | NIST | |
| 602.837 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.8d 2D | Measured | NIST | |
| 602.837 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.8d 2D | Measured | NIST | |
| 608.039 nm | 85 | B II | emission | 1s2.2p2 1S → 1s2.2s.3p 1P* | Measured | NIST | |
| 612.224 nm | N/A | B II | emission | 1s2.2p2 1S → 1s2.2s.3p 3P* | Measured | NIST | |
| 612.508 nm | 93 | B III | emission | 1s.2s.(3S).3s 4S → 1s.2s.(3S).3p 4P* | Measured | NIST | |
| 612.752 nm | N/A | B III | emission | 1s.2s.(3S).3s 4S → 1s.2s.(3S).3p 4P* | Measured | NIST | |
| 612.797 nm | N/A | B III | emission | 1s.2s.(3S).3s 4S → 1s.2s.(3S).3p 4P* | Measured | NIST | |
| 614.891 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.6f 3F* | Measured | NIST | |
| 614.891 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.6f 3F* | Measured | NIST | |
| 614.891 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.6f 3F* | Measured | NIST | |
| 614.891 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.6f 3F* | Measured | NIST | |
| 614.891 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.6f 3F* | Measured | NIST | |
| 614.891 nm | N/A | B II | emission | 1s2.2s.4d 3D → 1s2.2s.6f 3F* | Measured | NIST | |
| 617.867 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.8s 2S | Measured | NIST | |
| 617.936 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.8s 2S | Measured | NIST | |
| 618.638 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2p.3p 3D | Measured | NIST | |
| 618.638 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2p.3p 3D | Measured | NIST | |
| 618.638 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2p.3p 3D | Measured | NIST | |
| 619.359 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2p.3p 3D | Measured | NIST | |
| 619.359 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2p.3p 3D | Measured | NIST | |
| 619.735 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2p.3p 3D | Measured | NIST | |
| 622.745 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.7d 2D | Measured | NIST | |
| 622.815 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.7d 2D | Measured | NIST | |
| 622.815 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.7d 2D | Measured | NIST | |
| 624.4557 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.6f 2F* | Measured | NIST | |
| 624.4557 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.6f 2F* | Measured | NIST | |
| 624.4681 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.6f 2F* | Measured | NIST | |
| 628.551 nm | 30 | B II | emission | 1s2.2s.3d 1D → 1s2.2s.4p 1P* | Measured | NIST | |
| 634.927 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2s.6g 3G | Measured | NIST | |
| 634.927 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2s.6g 3G | Measured | NIST | |
| 634.927 nm | N/A | B II | emission | 1s2.2s.4f 3F* → 1s2.2s.6g 3G | Measured | NIST | |
| 635.676 nm | 1 | B II | emission | 1s2.2s.4f 1F* → 1s2.2s.6g 1G | Measured | NIST | |
| 643.151 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.7s 2S | Measured | NIST | |
| 643.225 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.7s 2S | Measured | NIST | |
| 652.056 nm | N/A | B II | emission | 1s2.2s.4s 3S → 1s2.2p.3s 3P* | Measured | NIST | |
| 652.959 nm | N/A | B II | emission | 1s2.2s.4s 3S → 1s2.2p.3s 3P* | Measured | NIST | |
| 653.371 nm | N/A | B II | emission | 1s2.2s.4s 3S → 1s2.2p.3s 3P* | Measured | NIST | |
| 656.269 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.6d 2D | Measured | NIST | |
| 656.345 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.6d 2D | Measured | NIST | |
| 656.345 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.6d 2D | Measured | NIST | |
| 657.112 nm | 0.5 | B II | emission | 1s2.2s.5p 1P* → 1s2.2p.3p 1D | Measured | NIST | |
| 671.765 nm | 0.5 | B II | emission | 1s2.2s.4d 1D → 1s2.2s.6f 1F* | Measured | NIST | |
| 677.866 nm | N/A | B I | emission | 2s2.4p 2P* → 2s.2p2 2P | Measured | NIST | |
| 677.895 nm | N/A | B I | emission | 2s2.4p 2P* → 2s.2p2 2P | Measured | NIST | |
| 678.401 nm | N/A | B I | emission | 2s2.4p 2P* → 2s.2p2 2P | Measured | NIST | |
| 678.431 nm | N/A | B I | emission | 2s2.4p 2P* → 2s.2p2 2P | Measured | NIST | |
| 678.614 nm | 0.5 | B II | emission | 1s2.2s.4p 1P* → 1s2.2s.5d 1D | Measured | NIST | |
| 681.95167 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.5f 2F* | Measured | NIST | |
| 681.95167 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.5f 2F* | Measured | NIST | |
| 681.96637 nm | N/A | B I | emission | 2s.2p2 2D → 2s2.5f 2F* | Measured | NIST | |
| 697.688 nm | N/A | B II | emission | 1s2.2s.3s 3S → 1s2.2s.3p 1P* | Measured | NIST | |
| 703.027 nm | 4 | B II | emission | 1s2.2s.3s 3S → 1s2.2s.3p 3P* | Measured | NIST | |
| 703.203 nm | 3 | B II | emission | 1s2.2s.3s 3S → 1s2.2s.3p 3P* | Measured | NIST | |
| 703.233 nm | 2 | B II | emission | 1s2.2s.3s 3S → 1s2.2s.3p 3P* | Measured | NIST | |
| 715.955 nm | N/A | B II | emission | 1s2.2p.3s 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 716.016 nm | N/A | B II | emission | 1s2.2p.3s 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 716.511 nm | N/A | B II | emission | 1s2.2p.3s 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 716.846 nm | N/A | B II | emission | 1s2.2p.3s 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 717.045 nm | N/A | B II | emission | 1s2.2p.3s 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 717.602 nm | N/A | B II | emission | 1s2.2p.3s 3P* → 1s2.2p.3p 3P | Measured | NIST | |
| 720.593 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.5d 2D | Measured | NIST | |
| 720.685 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.5d 2D | Measured | NIST | |
| 720.685 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.5d 2D | Measured | NIST | |
| 720.766 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.6s 2S | Measured | NIST | |
| 720.859 nm | N/A | B I | emission | 2s2.3p 2P* → 2s2.6s 2S | Measured | NIST | |
| 722.85 nm | N/A | B II | emission | 1s2.2s.4s 1S → 1s2.2s.5p 1P* | Measured | NIST |
Extended Properties
Covalent Radii (Extended)
- Covalent radius (Pyykkö)
- 85 pm
- Covalent radius (Pyykkö, double)
- 78 pm
- Covalent radius (Pyykkö, triple)
- 73 pm
Van der Waals Radii
- Truhlar
- 192 pm
- Batsanov
- 180 pm
- Alvarez
- 191 pm
- UFF
- 408.3 pm
- MM3
- 215 pm
- Dreiding
- 402 pm
Atomic & Metallic Radii
- Atomic radius (Rahm)
- 205 pm
- Metallic radius (C12)
- 98 pm
Numbering Scales
- Mendeleev
- 81
- Pettifor
- 86
- Glawe
- 86
Electronegativity Scales
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 4
- Robles–Bartolotti
- 4
Polarizability & Dispersion
- Dipole polarizability
- 20.5 a.u.
- Dipole polarizability (unc.)
- 0.1 a.u.
- C₆
- 99.5 Ha·Bohr6
- C₆ (Gould–Bučko)
- 99.2 Ha·Bohr6
Miedema Parameters
- Miedema molar volume
- 4.7 cm3/mol
- Miedema electron density
- 5
Supply Risk & Economics
- Production concentration
- 34
- Relative supply risk
- 5
- Political stability (top producer)
- 12
- Political stability (top reserve)
- 12
Phase Transitions & Allotropes
| Melting point | 2350.15 K |
| Boiling point | 4273.15 K |
Oxidation State Categories
Advanced Reference Data
Screening Constants (3)
| n | Orbital | σ |
|---|---|---|
| 1 | s | 0.3205 |
| 2 | p | 2.5786 |
| 2 | s | 2.4238 |
Crystal Radii Detail (3)
| Charge | CN | Spin | rcrystal (pm) | Origin |
|---|---|---|---|---|
| 3 | III | 15 | ||
| 3 | IV | 25 | ||
| 3 | VI | 41 | calculated, |
Isotope Decay Modes (30)
| Isotope | Mode | Intensity |
|---|---|---|
| 6 | 2p | — |
| 7 | p | 100% |
| 8 | B+ | 100% |
| 8 | B+A | 100% |
| 9 | p | 100% |
| 12 | B- | 100% |
| 12 | B-A | 0.6% |
| 13 | B- | 100% |
| 13 | B-n | 0.3% |
| 14 | B- | 100% |
X‑ray Scattering Factors (502)
| Energy (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1.48933 |
| 10.1617 | — | 1.48084 |
| 10.3261 | — | 1.4724 |
| 10.4931 | — | 1.46401 |
| 10.6628 | — | 1.45567 |
| 10.8353 | — | 1.44738 |
| 11.0106 | — | 1.43913 |
| 11.1886 | — | 1.43093 |
| 11.3696 | — | 1.42278 |
| 11.5535 | — | 1.41467 |
Additional Data
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
1.0×101 milligrams per kilogram
References (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
4.44 milligrams per liter
References (1)
Sources
Sources of this element.
The element is not found free in nature, but occurs as orthoboric acid usually found in certain volcanic spring waters and as borates in boron and colemantie.
Important sources of boron are ore rasorite (kernite) and tincal (borax ore). Both of these ores are found in the Mojave Desert. Tincal is the most important source of boron from the Mojave. Extensive borax deposits are also found in Turkey.
Boron exists naturally as 19.78% 10B isotope and 80.22% 11B isotope. High-purity crystalline boron may be prepared by the vapor phase reduction of boron trichloride or tribromide with hydrogen on electrically heated filaments. The impure or amorphous, boron, a brownish-black powder, can be obtained by heating the trioxide with magnesium powder.
Boron of 99.9999% purity has been produced and is available commercially. Elemental boron has an energy band gap of 1.50 to 1.56 eV, which is higher than that of either silicon or germanium.
References (1)
- [6] Boron https://periodic.lanl.gov/5.shtml
References
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Boron.
The element property data was retrieved from publications.