Niobium (Nb)
transition-metalSolid
Peso atomico standard
92,90637 uConfigurazione elettronica
[Kr] 5s1 4d4Punto di fusione
2476,85 °CPunto di ebollizione
4743,85 °CDensità
8570 kg/m³Stati di ossidazione
−3, −1, 0, +1, +2, +3, +4, +5Elettronegatività (Pauling)
1,6Energia di ionizzazione (1ª)
6,75885 eVAnno della scoperta
1801Raggio atomico
145 pmDettagli
Niobium is a refractory transition metal of group 5, chemically similar to tantalum and commonly occurring with it in oxide minerals. It is valued for its ability to strengthen steel at very small additions and for forming superconducting intermetallic compounds. In most compounds niobium is pentavalent, but lower oxidation states are well established, especially in halides and cluster chemistry.
Niobium is a shiny, white, soft, and ductile metal, and takes on a bluish cast when exposed to air at room temperatures for a long time. The metal starts to oxidize in air at 200°C, and when processed at even moderate temperatures must be placed in a protective atmosphere.
The name derives from the Greek mythological character Niobe, who was the daughter of Tantalus, because the elements niobium and tantalum were originally thought to be identical. Niobium was discovered in a black mineral from America called columbite by the British chemist and manufacturer Charles Hatchett in 1801 and he called the element columbium. In 1809, the English chemist William Hyde Wollaston claimed that columbium and tantalum were identical.
Forty years later, the German chemist and pharmacist, Heinrich Rose, determined that they were two different elements in 1846 and gave the name niobium because it was so difficult to distinguish it from tantalum. The name columbium continued to be used in America and niobium in Europe until IUPAC adopted the name niobium in 1949. Niobium was first isolated by the chemist C. W. Blomstrand in 1846.
The story of niobium's discovery is a bit confusing. The first governor of Connecticut, John Winthrop the Younger, discovered a new mineral around 1734. He named the mineral columbite ((Fe, Mn, Mg)(Nb, Ta)2O6) and sent a sample of it to the British Museum in London, England. The columbite sat in the museum's mineral collection for years until it was analyzed by Charles Hatchett in 1801. Hatchett could tell that there was an unknown element in the columbite, but he was not able to isolate it. He named the new element columbium. The fate of columbium took a drastic turn in 1809 when William Hyde Wollaston, an English chemist and physicist, compared the minerals columbite and tantalite ((Fe, Mn)(Ta, Nb)2O6) and declared that columbium was actually the element tantalum. This confusion arose because tantalum and niobium are similar metals, are always found together and are very difficult to isolate.
Niobium was rediscovered and renamed by Heinrich Rose in 1844 when he produced two new acids, niobic acid and pelopic acid, from samples of columbite and tantalite. These acids are very similar to each other and it took another twenty-two years and a Swiss chemist named Jean Charles Galissard de Marignac to prove that these were two distinct chemicals produced from two different elements. Metallic niobium was finally isolated by the Swedish chemist Christian Wilhelm Blomstrand in 1864. Today, niobium is primarily obtained from the minerals columbite and pyrochlore ((Ca, Na)2Nb2O6(O, OH, F)).
Named after Niobe, the daughter of Tantalu. Discovered in 1801 by Hatchett in an ore sent to England. The metal was first prepared in 1864 by Blomstrand, who reduced the chloride by heating it in a hydrogen atmosphere. The name niobium was adopted by the International Union of Pure and Applied Chemicstry (IUPAC) in 1950 after 100 years of controversy. Many leading chemical societies and government organizations refer to it by this name. Most metallurgists, leading metal societies, and all but one of the leading U.S. commercial producers, however, still refer to the metal as "columbium."
Pure niobium is a soft, ductile, lustrous gray metal when freshly prepared. It is solid under ordinary conditions and develops a thin protective oxide film in air. The metal has a high melting point and can be worked when sufficiently pure, but interstitial oxygen, nitrogen, or hydrogen can make it less ductile.
The largest use of niobium is as ferroniobium in high-strength low-alloy steels, where small additions improve strength, toughness, and grain control. Niobium-bearing steels are used in pipelines, structural steel, automotive parts, and some pressure vessels. Niobium-titanium and niobium-tin superconductors are used in magnets for MRI systems, particle accelerators, and research instruments. Niobium is also used in some nickel-base superalloys, welding alloys, corrosion-resistant equipment, and electronic components such as niobium capacitors.
Niobium is used as an alloying agent and for jewelry, but perhaps its most interesting applications are in the field of superconductivity. Superconductive wire can be made from an alloy of niobium and titanium which can then be used to make superconductive magnets. Other alloys of niobium, such as those with tin and aluminum, are superconductive as well. Pure niobium is itself a superconductor when it is cooled below 9.25 K (-442.75°F). Superconductive niobium cavities are at the heart of a machine built at the Thomas Jefferson National Accelerator Facility. This machine, called an electron accelerator, is used by scientists to study the quark structure of matter. The accelerator's 338 niobium cavities are bathed in liquid helium and accelerate electrons to nearly the speed of light.
Niobium is used in arc-welding rods for stabilized grades of stainless steel. Thousands of pounds of niobium have been used in advanced air frame systems such as were used in the Gemini space program. The element has superconductive properties; superconductive magnets have been made with Nb-Zr wire, which retains its superconductivity in strong magnetic fields. This type of application offers hope of direct large-scale generation of electric power. Niobium is also commonly used for jewelry.
Isotopes in Biology
95Nb (with a half-life of 35 days) and 95Nb-oxalates have been used to study the absorption, retention and distribution of niobium in the body [309] F. R. Mraz, G. R. Eisele. Radiat. Res.72, 533 (1977)., [310] F. Paquet, P. Houpert, M. Verry, G. Grillon, J. D. Harrison, H. Métivier. Radiat. Prot. Dosim.79, 191 (1998)..
Isotopes in Earth/Planetary Science
Nuclear physicists are trying to study the generation of new isotopes and their elements in stars (astrophysical nucleosynthesis) via the rapid neutron capture process (r-process). Physicists at the Radioactive Isotope Beam Facility (RIBF) of the RIKEN Nishina Center for Accelerator-Based Science in Wako, Japan, have begun creating and studying highly neutron-rich isotopes that are thought to only be produced by the r-process. The data for many neutron-rich isotopes is incomplete, and the RIKEN team is filling in key missing information that is needed to simulate the r-process (including information on the half-lives of the neutron-rich isotopes). So far, the half-lives of 38 neutron-rich isotopes have been measured from krypton to technetium, including 111Nb and 112Nb. When the missing information has been obtained, physicists will have a better understanding of the r-process and how elements are created [311] RIKEN Research. The Importance of Fundamental Measurements, RIKEN Research (2017), Feb. 26; http://www.riken.jp/en/research/rikenresearch/highlights/6600/., [312] S. Nishimura, Z. Li, H. Watanabe, K. Yoshinaga, T. Sumikama, T. Tachibana, K. Yamaguchi, M. Kurata-Nishimura, G. Lorusso, Y. Miyashita, A. Odahara, H. Baba, J. S. Berryman, N. Blasi, A. Bracco, F. Camera, J. Chiba, P. Doornenbal, S. Go, T. Hashimoto, S. Hayakawa, C. Hinke, E. Ideguchi, T. Isobe, Y. Ito, D. G. Jenkins, Y. Kawada, N. Kobayashi, Y. Kondo, R. Krücken, S. Kubono, T. Nakano, H. J. Ong, S. Ota, Z. Podolyák, H. Sakurai, H. Scheit, K. Steiger, D. Steppenbeck, K. Sugimoto, S. Takano, A. Takashima, K. Tajiri, T. Teranishi, Y. Wakabayashi, P. M. Walker, O. Wieland, H. Yamaguchi. Phys. Rev. Lett.106, 052502 (2011)..
Isotopes in Medicine
95Nb and 95mNb (with a half-life of 3.6 days) have been used in tumor research and tumor imaging studies (Fig. IUPAC.41.1) [313] A. Ando, I. Ando. J. Radiat. Res.31, 97 (1990)., [314] A. Ando, I. Ando. Acta Radiol. Suppl.374, 65 (1990)., [315] V. Radchenko, P. Bouziotis, G. Loudos, S. Xanthopoulos, H. Hauser, M. Esienhut, B. Ponsard, F. Roesch. J. Labelled Comp. Radiopharm.56, S69 (2013).. The m in the superscript of 95mNb indicates a metastable state of the isotope.
Niobium chemistry is dominated by the +5 oxidation state. Niobium pentoxide, Nb₂O₅, is the most important oxide and a common intermediate in extraction and materials processing. Niobium pentachloride, NbCl₅, is a volatile Lewis-acidic halide used in synthesis and as a precursor to other niobium compounds. Lower halides such as niobium tetrachloride, NbCl₄, and cluster compounds contain Nb–Nb bonding. Carbides and nitrides, including niobium carbide, NbC, and niobium nitride, NbN, are hard refractory materials; NbN can be superconducting depending on composition and structure.
See more information at the Niobium compound page.
Compact niobium metal is generally of low chemical toxicity, but fine powder can burn and presents a dust exposure hazard. Machining dusts, fumes from welding, and soluble or reactive niobium compounds should be handled as industrial particulates or corrosive chemicals according to their form. Natural niobium consists essentially of stable ⁹³Nb, while radioactive niobium isotopes are mainly research or activation products and have isotope-specific radiological hazards.
Niobium occurs at low concentrations in the crust, chiefly in resistant oxide minerals such as pyrochlore and columbite rather than as native metal. It is not known to have an essential biological role. Under surface conditions niobium is relatively immobile because pentavalent niobium forms insoluble oxides and strongly sorbs to mineral surfaces. Mining and processing residues are the main localized environmental concern.
Niobium is produced mainly from pyrochlore concentrates, commonly converted to ferroniobium for direct steelmaking use. Separation from tantalum can be important in ores where both elements occur, but the dominant niobium supply is tied to large carbonatite-hosted deposits. Demand is strongly linked to steel production and infrastructure. Recycling occurs indirectly through niobium-bearing steel scrap and specialty alloy scrap, although dilute additions make full element-specific recovery difficult. Substitution is possible in some steels with vanadium, titanium, or molybdenum, but performance and processing trade-offs limit direct replacement.
The element is found in niobite (or columbite), niobite-tantalite, parochlore, and euxenite. Large deposits of niobium have been found associated with carbonatites (carbon-silicate rocks), as a constituent of parochlore. Extensive ore reserves are found in Canada, Brazil, Nigeria, Zaire, and in Russia.
Niobium is a trace cosmic element produced mainly by neutron-capture processes in earlier generations of stars. It is less abundant than neighboring lighter transition metals and is not a major rock-forming element in planetary materials. In meteorites and terrestrial rocks it behaves as a refractory lithophile element and tends to remain with oxide and silicate phases rather than metallic iron.
- Niobium was long known as columbium, and that name persisted in parts of industry for many years.
- The stable isotope ⁹³Nb makes natural niobium nearly monoisotopic.
- Niobium microalloying can change steel properties at additions well below one percent.
- Niobium and tantalum are difficult to separate because their ionic sizes and chemistry are very similar.
- The superconducting compound niobium-tin is Nb₃Sn.
Immagini
Proprietà
Fisiche
- Raggio atomico (empirico)
- 145 pm Confronta Raggio atomico (empirico) di tutti gli elementi →
- Raggio covalente
- 164 pm Confronta Raggio covalente di tutti gli elementi →
- Raggio di van der Waals
- 207 pm Confronta Raggio di van der Waals di tutti gli elementi →
- Raggio metallico
- 134 pm Confronta Raggio metallico di tutti gli elementi →
- Densità
- 8570 kg/m³ Confronta Densità di tutti gli elementi →
- Volume molare
- 0,0108 L/mol
- Fase in condizioni STP
- Solido Confronta Fase in condizioni STP di tutti gli elementi →
- Punto di fusione
- 2476,85 °C Confronta Punto di fusione di tutti gli elementi →
- Punto di ebollizione
- 4743,85 °C Confronta Punto di ebollizione di tutti gli elementi →
- Conducibilità termica
- 53,7 W/(m·K) Confronta Conducibilità termica di tutti gli elementi →
- Capacità termica specifica
- 0,265 J/(g·K) Confronta Capacità termica specifica di tutti gli elementi →
- Capacità termica molare
- 24,6 J/(mol·K) Confronta Capacità termica molare di tutti gli elementi →
- Struttura cristallina
- Cubica a corpo centrato Confronta Struttura cristallina di tutti gli elementi →
Chimiche
- Elettronegatività (Pauling)
- 1,6 Confronta Elettronegatività (Pauling) di tutti gli elementi →
- Elettronegatività (Allen)
- 1,41
- Affinità elettronica
- 0,893 eV
- Energia di ionizzazione (1ª)
- 6,75885 eV Confronta Energia di ionizzazione (1ª) di tutti gli elementi →
- Energia di ionizzazione (2ª)
- 14,320049 eV Confronta Energia di ionizzazione (2ª) di tutti gli elementi →
- Energia di ionizzazione (3ª)
- 25,040086 eV Confronta Energia di ionizzazione (3ª) di tutti gli elementi →
- Energia di ionizzazione (4ª)
- 37,611129 eV Confronta Energia di ionizzazione (4ª) di tutti gli elementi →
- Energia di ionizzazione (5ª)
- 50,572974 eV Confronta Energia di ionizzazione (5ª) di tutti gli elementi →
- Stati di ossidazione
- −3, −1, 0, +1, +2, +3, +4, +5 Confronta Stati di ossidazione di tutti gli elementi →
- Elettroni di valenza
- 5 Confronta Elettroni di valenza di tutti gli elementi →
- Configurazione elettronica
- [Kr] 5s1 4d4
Termodinamiche
- Calore di fusione
- 0,27776338 eV Confronta Calore di fusione di tutti gli elementi →
- Calore di vaporizzazione
- 7,151371 eV Confronta Calore di vaporizzazione di tutti gli elementi →
- Calore di sublimazione
- 7,617764 eV
- Calore di atomizzazione
- 7,617764 eV
- Entalpia di atomizzazione
- 7,597036 eV
Nucleari
- Protoni
- 41 Confronta Protoni di tutti gli elementi →
- Neutroni
- 52 Confronta Neutroni di tutti gli elementi →
- Isotopi noti
- 38 Confronta Isotopi noti di tutti gli elementi →
- Isotopi stabili
- 1 Confronta Isotopi stabili di tutti gli elementi →
- Isotopo più stabile
- Nb-93
- Anno della scoperta
- 1801
Abbondanza
- Abbondanza (crosta terrestre)
- 20 mg/kg Confronta Abbondanza (crosta terrestre) di tutti gli elementi →
- Abbondanza (oceano)
- 1 × 10−5 mg/L Confronta Abbondanza (oceano) di tutti gli elementi →
Struttura cristallina
- Costante reticolare a
- 330 pm
Struttura elettronica
- Elettroni per guscio
- 2, 8, 18, 12, 1 Confronta Elettroni per guscio di tutti gli elementi →
Identificativi
- Numero CAS
- 7440-03-1 Confronta Numero CAS di tutti gli elementi →
- Simbolo di termine
- 6D1/2
- InChI
- InChI=1S/Nb
- Chiave InChI
- GUCVJGMIXFAOAE-UHFFFAOYSA-N
Configurazione elettronica Misurato
Nb: 4d⁴ 5s¹[Kr] 4d⁴ 5s¹1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d⁴ 5s¹Modello atomico
Gli isotopi modificano il numero di neutroni, la massa e la stabilità — non la configurazione elettronica di un atomo neutro.
Modello atomico schematico, non in scala.
Impronta atomica
Spettro di emissione / assorbimento
Distribuzione isotopica
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita |
|---|---|---|---|
| 93 Stabile | 92,906373 ± 0,000002 | 100,0000% | Stabile |
Fase / Stato
Motivo: 2451,8 °C sotto il punto di fusione (2476,85 °C)
Schema non in scala
Punti di transizione di fase
Energie di transizione
Energia necessaria per fondere 1 mol al punto di fusione
Energia necessaria per vaporizzare 1 mol al punto di ebollizione
Energia necessaria per sublimare 1 mol al punto di sublimazione
Densità
In condizioni standard
In condizioni standard
Spettri atomici
Sono visualizzati 10 di 41. Ordinamento per carica ionica crescente.
Righe disponibili ?
| Ione | Carica | Righe totali | Probabilità di transizione | Designazioni dei livelli |
|---|---|---|---|---|
| Nb I | 0 | 509 | 0 | 0 |
| Nb II | +1 | 150 | 0 | 0 |
| Nb III | +2 | 108 | 0 | 0 |
| Nb IV | +3 | 819 | 819 | 819 |
| Nb V | +4 | 12 | 0 | 0 |
Livelli disponibili ?
| Ione | Carica | Livelli |
|---|---|---|
| Nb I | 0 | 395 |
| Nb II | +1 | 354 |
| Nb III | +2 | 189 |
| Nb IV | +3 | 183 |
| Nb V | +4 | 31 |
| Nb VI | +5 | 105 |
| Nb VII | +6 | 32 |
| Nb VIII | +7 | 2 |
| Nb IX | +8 | 2 |
| Nb X | +9 | 2 |
Raggi ionici
| Carica | Coordinazione | Spin | Raggio |
|---|---|---|---|
| +3 | 6 | N/D | 72 pm |
| +4 | 6 | N/D | 68 pm |
| +4 | 8 | N/D | 79 pm |
| +5 | 4 | N/D | 48 pm |
| +5 | 6 | N/D | 64 pm |
| +5 | 7 | N/D | 69 pm |
| +5 | 8 | N/D | 74 pm |
Composti
Isotopi (1)
Eighteen isotopes of niobium are known. The metal can be isolated from tantalum, and prepared in several ways.
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita | Modalità di decadimento | |
|---|---|---|---|---|---|
| 93 Stabile | 92,906373 ± 0,000002 | 100,0000% | Stabile | stable |
Righe spettrali
| Lunghezza d'onda (nm) | Intensità | Stadio di ionizzazione | Tipo | Transizione | Accuratezza | Fonte | |
|---|---|---|---|---|---|---|---|
| 382.5416 nm | 5000 | Nb IV | emission | 4d.5d 3P → 4d.6p 1P* | Misurata | NIST | |
| 382.5694 nm | 200000 | Nb IV | emission | 4d.6p 1F* → 4d.6d 3D | Misurata | NIST | |
| 382.5875 nm | 250000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 3D | Misurata | NIST | |
| 383.106 nm | 15000 | Nb IV | emission | 4d.5d 3D → 4d.6p 1D* | Misurata | NIST | |
| 385.2874 nm | 60000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 3D | Misurata | NIST | |
| 385.5325 nm | 10000 | Nb IV | emission | 4d.6p 1P* → 4d.6d 3P | Misurata | NIST | |
| 386.9546 nm | 8000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 1P | Misurata | NIST | |
| 387.5455 nm | 100000 | Nb IV | emission | 4d.5d 3G → 4d.6p 1D* | Misurata | NIST | |
| 388.2203 nm | 60000 | Nb IV | emission | 4d.6p 1P* → 4d.6d 1S | Misurata | NIST | |
| 389.8028 nm | 100000 | Nb IV | emission | 4d.5d 3S → 4d.6p 3P* | Misurata | NIST | |
| 390.0115 nm | 25000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 3D | Misurata | NIST | |
| 391.6922 nm | 8000 | Nb IV | emission | 4d.5d 3F → 4d.6p 1F* | Misurata | NIST | |
| 392.1878 nm | 5000 | Nb IV | emission | 4d.5d 1P → 4d.6p 3D* | Misurata | NIST | |
| 394.057 nm | 25000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 3D | Misurata | NIST | |
| 394.3315 nm | 20000 | Nb IV | emission | 4d.5d 3F → 4d.6p 3F* | Misurata | NIST | |
| 398.5759 nm | 5000 | Nb IV | emission | 4d.(2D<3/2>).6s 2[3/2] → 4d.6p 1P* | Misurata | NIST | |
| 400.1839 nm | 4000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 3D | Misurata | NIST | |
| 403.2233 nm | 40000 | Nb IV | emission | 4d.5d 3F → 4d.6p 3D* | Misurata | NIST | |
| 404.998 nm | 10000 | Nb IV | emission | 4d.5d 3F → 4d.6p 3F* | Misurata | NIST | |
| 405.2616 nm | 15000 | Nb IV | emission | 4d.5d 1P → 4d.6p 1D* | Misurata | NIST | |
| 406.3412 nm | 200000 | Nb IV | emission | 4d.5d 3F → 4d.6p 3F* | Misurata | NIST | |
| 406.4694 nm | N/D | Nb IV | emission | 4d.6p 1P* → 4d.6d 1D | Misurata | NIST | |
| 409.6529 nm | 7000 | Nb IV | emission | 4d.6p 3P* → 4d.6d 3D | Misurata | NIST | |
| 459.6 nm | N/D | ID 841 | emission | 2p 2P* → 2s 2S | Misurata | NIST |
Proprietà estese
Raggi covalenti (dati estesi)
- Raggio covalente (Pyykkö)
- 147 pm
- Raggio covalente (Pyykkö, legame doppio)
- 125 pm
- Raggio covalente (Pyykkö, legame triplo)
- 116 pm
Raggi di van der Waals
- Batsanov
- 215 pm
- Alvarez
- 256 pm
- UFF
- 316,5 pm
- MM3
- 243 pm
Raggi atomici e metallici
- Raggio atomico (Rahm)
- 251 pm
- Raggio metallico (C12)
- 146 pm
Scale di numerazione
- Mendeleev
- 48
- Pettifor
- 52
- Glawe
- 53
Scale di elettronegatività
- Ghosh
- 0
- Miedema
- 4
- Gunnarsson–Lundqvist
- 4
- Robles–Bartolotti
- 2
Polarizzabilità e dispersione
- Polarizzabilità dipolare
- 98 a.u.
- Polarizzabilità dipolare (inc.)
- 8 a.u.
- C₆ (Gould–Bučko)
- 1140 Ha·Bohr6
Parametri di Miedema
- Volume molare di Miedema
- 10,87 cm3/mol
- Densità elettronica di Miedema
- 4
Rischio di approvvigionamento ed economia
- Concentrazione della produzione
- 98
- Rischio relativo di approvvigionamento
- 8
- Distribuzione delle riserve
- 97
- Stabilità politica (principale produttore)
- 48
- Stabilità politica (principale detentore di riserve)
- 48
Transizioni di fase e allotropi
| Punto di fusione | 2750,15 K |
| Punto di ebollizione | 5014,15 K |
Categorie degli stati di ossidazione
Dati di riferimento avanzati
Costanti di schermaggio (10)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 0,8577 |
| 2 | p | 4,0178 |
| 2 | s | 10,8748 |
| 3 | d | 14,753 |
| 3 | p | 16,3844 |
| 3 | s | 15,8285 |
| 4 | d | 29,7624 |
| 4 | p | 26,9156 |
| 4 | s | 25,7172 |
| 5 | s | 35,079 |
Dettaglio dei raggi cristallini (7)
| Carica | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 3 | VI | 86 | ||
| 4 | VI | 82 | from r^3 vs V plots, estimated, | |
| 4 | VIII | 93 | ||
| 5 | IV | 62 | calculated, | |
| 5 | VI | 78 | ||
| 5 | VII | 83 | calculated, | |
| 5 | VIII | 88 |
Modalità di decadimento degli isotopi (67)
| Isotopo | Modalità | Intensità |
|---|---|---|
| 79 | p | — |
| 79 | B+ | — |
| 79 | B+p | — |
| 80 | p | — |
| 80 | B+ | — |
| 80 | B+p | — |
| 81 | p | — |
| 81 | B+ | — |
| 81 | B+p | — |
| 82 | B+ | 100% |
Fattori di diffusione dei raggi X (757)
| Energia (eV) | f₁ | f₂ |
|---|---|---|
| 0,5 | — | 0,09113 |
| 0,5079 | — | 0,09258 |
| 0,516 | — | 0,09406 |
| 0,5242 | — | 0,09557 |
| 0,5325 | — | 0,0971 |
| 0,5409 | — | 0,09865 |
| 0,5495 | — | 0,10023 |
| 0,5582 | — | 0,10161 |
| 0,5671 | — | 0,103 |
| 0,5761 | — | 0,10441 |
Dati aggiuntivi
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
2.0×101 milligrams per kilogram
Riferimenti (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
1×10-5 milligrams per liter
Riferimenti (1)
Sources
Sources of this element.
The element is found in niobite (or columbite), niobite-tantalite, parochlore, and euxenite. Large deposits of niobium have been found associated with carbonatites (carbon-silicate rocks), as a constituent of parochlore. Extensive ore reserves are found in Canada, Brazil, Nigeria, Zaire, and in Russia.
Riferimenti (1)
- [6] Niobium https://periodic.lanl.gov/41.shtml
Riferimenti
(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 Niobium.
The element property data was retrieved from publications.