Iron (Fe)
transition-metalSolid
Peso atomico standard
55,845 uConfigurazione elettronica
[Ar] 4s2 3d6Punto di fusione
1537,85 °CPunto di ebollizione
2860,85 °CDensità
7874 kg/m³Stati di ossidazione
−4, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7Elettronegatività (Pauling)
1,83Energia di ionizzazione (1ª)
7,902468 eVAnno della scoperta
N/DRaggio atomico
140 pmDettagli
Iron is a first-row transition metal and one of the central elements of technology and biology. It forms strong, workable alloys, especially with carbon, and has accessible Fe²⁺ and Fe³⁺ redox chemistry. In Earth materials it is a major constituent of the core, mantle minerals, and many ores. Its magnetic behavior and ability to bind small molecules in metalloproteins give it importance beyond structural metal use.
The pure metal is very reactive chemically and rapidly corrodes, especially in moist air or at elevated temperatures. It has four allotropic forms or ferrites, known as alpha, beta, gamma, and omega, with transition points at 700, 928, and 1530C. The alpha form is magnetic, but when transformed into the beta form, the magnetism disappears although the lattice remains unchanged. The relations of these forms are peculiar. Pig iron is an alloy containing about 3 percent carbon with varying amounts of sulfur, silicon, manganese, and phosphorus.
Iron is hard, brittle, fairly fusible, and is used to produce other alloys, including steel. Wrought iron contains only a few tenths of a percent of carbon, is tough, malleable, less fusible, and usually has a "fibrous" structure.
Carbon steel is an alloy of iron with small amounts of Mn, S, P, and Si. Alloy steels are carbon steels with other additives such as nickel, chromium, vanadium, etc. Iron is a cheap, abundant, useful, and important metal.
The name derives from the Anglo-Saxon iron of unknown origin. The element has been known from prehistoric times. The symbol Fe is derived from the Latin ferrum for "firmness". It is of interest to note that 56Fe requires more energy to be formed than any other nuclide. It is, therefore, the ultimate endproduct of stellar nuclear fusion.
Archaeological evidence suggests that people have been using iron for at least 5000 years. Iron is the cheapest and one of the most abundant of all metals, comprising nearly 5.6% of the earth's crust and nearly all of the earth's core. Iron is primarily obtained from the minerals hematite (Fe2O3) and magnetite (Fe3O4). The minerals taconite, limonite (FeO(OH)·nH2O) and siderite (FeCO3) are other important sources.
Latin ferrum. Iron was used prehistorically:
▸ Iron is mentioned numerous times in the Old Testament of the Bible.
▸ A remarkable iron pillar, dating to about A.D. 400, remains standing today in Delhi, India. This solid shaft of wrought iron is about 7 1/4 m high by 40 cm in diameter. Corrosion to the pillar has been minimal although it has been exposed to the weather since its creation.
Pure iron is a lustrous, silvery-gray metal that tarnishes in moist air. At ordinary conditions it is solid, dense, malleable, and ferromagnetic. Commercial iron usually contains carbon and other impurities that strongly affect hardness, corrosion, and color of the surface.
Most iron is used as steel or cast iron rather than as the pure element. Carbon steels, stainless steels, and alloy steels are used in buildings, vehicles, machinery, tools, pipelines, rails, ships, and electrical equipment. Wrought iron was historically important for gates, chains, and structural work but is now a specialty material. Finely divided iron is used in some chemical reductions and in powder metallurgy, and iron cores and laminations remain important in magnetic devices.
Huge amounts of iron are used to make steel, an alloy of iron and carbon. Steel typically contains between 0.3% and 1.5% carbon, depending on the desired characteristics. The addition of other elements can give steel other useful properties. Small amounts of chromium improves durability and prevents rust (stainless steel); nickel increases durability and resistance to heat and acids; manganese increases strength and resistance to wear; molybdenum increases strength and resistance to heat; tungsten retains hardness at high temperatures; and vanadium increases strength and springiness. Steel is used to make paper clips, skyscrapers and everything in between.
In addition to helping build the world around us, iron helps keep plants and animals alive. Iron plays a role in the creation of chlorophyll in plants and is an essential part of hemoglobin, the substance that carries oxygen within red blood cells. Iron sulfate (FeSO4) is used to treat the blood disease anemia.
Iron is a vital constituent of plant and animal life and works as an oxygen carrier in hemoglobin.
Taconite is becoming increasingly important as a commercial ore. The pure metal is not often encountered in commerce, but is usually alloyed with carbon or other metals.
Isotopes in Biology
Natural iron enriched in its least abundant stable isotopes, 57Fe and 58Fe, are used as a tracer in human studies to assess absorption, excretion, distribution, and utilization of iron in basic and applied research [108] World Nuclear Association. Radioisotopes in Industry: Industrial Uses of Radioisotopes, World Nuclear Association (2014), Feb. 24; http://www.world-nuclear.org/info/inf56.html., [109] Australian Government, Australian Nuclear Science and Technology Organisation (Ansto). [Radioisotopes]:/their Role in Society Today/, Australian Government, Australian Nuclear Science and Technology Organisation (Ansto) (2014), Feb. 24; http://www.ansto.gov.au/__data/assets/pdf_file/0018/3564/Radioisotopes.pdf., [110] AUS-e-TUTE for Astute Science Students. Chemistry Tutorial: Summary of Radioactive Particles, Isotopes, Properties and Uses, AUS-e-TUTE for Astute Science Students (2014), Feb. 24; http://www.ausetute.com.au/nuclesum.html., [214] Z. Chen, I. J. Griffin, L. M. Plumlee, S. A. Abrams. J. Nutr.135, 1790 (2005)., [215] S. A. Abrams. Am. J. Clin. Nutr.70, 955 (1999)., [216] N. Dauphas, O. Rouxel. Mass Spectrom. Rev.25, 515 (2006).. The two radioisotopes, 55Fe and 59Fe, have sufficiently long half-lives of 2.75 years and 44.5 days, respectively, to be used as tracers, but potential health and environmental hazards limit their use to diagnostic applications in patient care (i.e. disorders of blood and of iron metabolism) [110] AUS-e-TUTE for Astute Science Students. Chemistry Tutorial: Summary of Radioactive Particles, Isotopes, Properties and Uses, AUS-e-TUTE for Astute Science Students (2014), Feb. 24; http://www.ausetute.com.au/nuclesum.html., [215] S. A. Abrams. Am. J. Clin. Nutr.70, 955 (1999)., [216] N. Dauphas, O. Rouxel. Mass Spectrom. Rev.25, 515 (2006)..
Isotopes in Earth/Planetary Science
60Fe is an extinct radionuclide with a half-life of 2.6×106 years that has fully decayed to 60Ni since formation of the Solar System. The distribution of the product (radiogenic) 60Ni in extraterrestrial material, such as meteorites, has been used to gain insight into the early history of the Solar System [216] N. Dauphas, O. Rouxel. Mass Spectrom. Rev.25, 515 (2006).. Because molecules, atoms, and ions of the stable isotopes of iron possess slightly different physical and chemical properties, they commonly will be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. There are measureable variations in the isotopic abundances of iron in natural terrestrial materials (Fig. IUPAC.26.1). Small variations in stable iron isotopic compositions caused by physical and chemical isotopic fractionation processes have been used to study mass transfer processes in nature and chemical equilibria [17] T. B. Coplen, J. A. Hopple, J. K. Böhlke, H. S. Peiser, S. E. Rieder, H. R. Krouse, K. J. R. Rosman, T. Ding, R. D. Vocke, K. Revesz, A. Lamberty, P. D. P. Taylor, P. D. Bièvre. United States Geological Survey Water-Resources Investigations Report, 01-4222, (2002)., [216] N. Dauphas, O. Rouxel. Mass Spectrom. Rev.25, 515 (2006)., [217] United States Geological Survey. Resources on Isotopes-Periodic Table-Iron, United States Geological Survey (2014), Feb. 25; http://wwwrcamnl.wr.usgs.gov/isoig/period/fe_iig.html..
Isotopes in Industry
55Fe is a beta emitting nuclide that serves as an electron source together with 63Ni (with a half-life of 99 years) in electron-capture detectors. Electron-capture detectors are used as thickness gauges or as detectors for organic analytes in gas chromatography [218] P. Cassettea, T. Altzitzogloub, R. Brodac, R. Colléd, P. Dryake, P. de Felicef, E. Guntherg, J. M. Los Arcosh, G. Rateli, B. Simpsonj, F. Verrezen. Appl. Radiat. Isot.49, 1403 (1998)..
Isotopes in Medicine
52Fe, with a half-life of 8.3 h, emits positrons and is used in positron emission tomography (PET) studies. It can be produced in a cyclotron from stable 50Cr by alpha particle capture [99] World Nuclear Association. Radioisotopes in Medicine, World Nuclear Association (2014), Feb. 23; http://www.world-nuclear.org/info/inf55.html., [219] M. Bruehlmeier, K. L. Leenders, P. Vontobel, C. Calonder, A. Antonini, A. Weindl. J. Nucl. Med.41, 781 (2000)., [220] A. Agool, A. W. Glaudemans, H. H. Boersma, R. A. Dierckx, E. Vellenga, R. H. Slart. Eur. J. Nucl. Med. Mol. Imaging38, 166 (2011)..
Isotopes Used as a Source of Radioactive Isotope(s)
Stable 56Fe is used for production of radioactive 55Co (with a half-life of about 18 h), as an emitter of positrons for PET applications using the reaction 56Fe (p, 2n) 55Co [221] S. Spellerberg, P. Reimer, G. Blessing, H. H. Coenen, S. M. Qaim. Appl. Radiat. Isot.49, 1519 (1998)., [222] F. Haddad, L. Ferrer, A. Guertin, T. Carlier, N. Michel, J. Barbet, J. F. Chatal. Eur. J. Nucl. Med. Mol. Imaging35, 1377 (2008)..
Iron commonly occurs in the +2 and +3 oxidation states, with interconversion between Fe²⁺ and Fe³⁺ central to its aqueous and biological chemistry. Important oxides include magnetite (Fe₃O₄), hematite (Fe₂O₃), and wüstite (FeO), while hydrated iron oxides and oxyhydroxides dominate rust and many soils. Iron forms salts such as iron(II) sulfate (FeSO₄) and iron(III) chloride (FeCl₃). Carbonyl chemistry includes iron pentacarbonyl (Fe(CO)₅), and organometallic chemistry is exemplified by ferrocene (Fe(C₅H₅)₂).
See more information at the Iron compound page.
Metallic iron is not highly toxic and iron is an essential nutrient, but excess intake or injection can be dangerous. Iron dust can irritate the lungs and is combustible when finely divided. Molten iron presents severe thermal hazards, and ironworking fumes may contain hazardous oxides or alloying-metal compounds. Soluble iron salts can be corrosive or harmful in concentrated form, especially to children.
Iron is abundant in rocks, soils, sediments, and natural waters, where it cycles between reduced Fe²⁺ and oxidized Fe³⁺ forms according to oxygen level, pH, and microbial activity. Iron oxides and oxyhydroxides bind phosphate, arsenic, and many trace metals, affecting their mobility. In some ocean regions, dissolved iron limits phytoplankton growth. Weathering, hydrothermal fluids, mining, and corrosion all redistribute iron locally.
Iron has one of the largest industrial supply chains of any element. It is produced mainly by mining iron ores such as hematite and magnetite, concentrating them where needed, and reducing the oxides in blast furnaces or direct-reduction processes before steelmaking. Scrap recycling is highly developed because steel can be remelted repeatedly, although composition control is important. Demand is tied to construction, transport, manufacturing, and infrastructure, and substitution is usually limited where low cost, strength, and availability are required.
Iron is a relatively abundant element in the universe. It is found in the sun and many types of stars in considerable quantity. Its nuclei are very stable. Iron is a principal component of a meteorite class known as siderites and is a minor constituent of the other two meteorite classes. The core of the earth 2150 miles in radius is thought to be largely composed of iron with about 10 percent occluded hydrogen. The metal is the fourth most abundant element, by weight that makes up the crust of the earth.
The most common ore is hematite, which is frequently seen as black sands along beaches and banks of streams.
Iron is cosmically common because nuclei near iron and nickel are strongly bound products of stellar nucleosynthesis. It is made in massive stars and dispersed by supernovae, with additional contributions from explosive stellar events. In rocky planets it is a major dense component; Earth’s core is dominated by iron alloyed with nickel and lighter elements. Iron lines are also important in astronomical spectroscopy.
- Iron has several allotropes; the change from body-centered to face-centered cubic structure is central to steel heat-tLE
- Stainless steel resists rust because chromium forms a protective oxide film, not because the iron is absent.
- Meteoric iron was worked by some cultures before large-scale smelting of terrestrial ores.
- Hemoglobin uses iron to bind O₂ reversibly without normally oxidizing it completely.
- Iron pentacarbonyl is a volatile liquid despite containing a transition metal.
Immagini
Proprietà
Fisiche
- Raggio atomico (empirico)
- 140 pm Confronta Raggio atomico (empirico) di tutti gli elementi →
- Raggio covalente
- 132 pm Confronta Raggio covalente di tutti gli elementi →
- Raggio di van der Waals
- 194 pm Confronta Raggio di van der Waals di tutti gli elementi →
- Raggio metallico
- 117 pm Confronta Raggio metallico di tutti gli elementi →
- Densità
- 7874 kg/m³ Confronta Densità di tutti gli elementi →
- Volume molare
- 0,0071 L/mol
- Fase in condizioni STP
- Solido Confronta Fase in condizioni STP di tutti gli elementi →
- Punto di fusione
- 1537,85 °C Confronta Punto di fusione di tutti gli elementi →
- Punto di ebollizione
- 2860,85 °C Confronta Punto di ebollizione di tutti gli elementi →
- Conducibilità termica
- 80,4 W/(m·K) Confronta Conducibilità termica di tutti gli elementi →
- Capacità termica specifica
- 0,449 J/(g·K) Confronta Capacità termica specifica di tutti gli elementi →
- Capacità termica molare
- 25,1 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)
- 1,83 Confronta Elettronegatività (Pauling) di tutti gli elementi →
- Elettronegatività (Allen)
- 1,8
- Affinità elettronica
- 0,151 eV
- Energia di ionizzazione (1ª)
- 7,902468 eV Confronta Energia di ionizzazione (1ª) di tutti gli elementi →
- Energia di ionizzazione (2ª)
- 16,199266 eV Confronta Energia di ionizzazione (2ª) di tutti gli elementi →
- Energia di ionizzazione (3ª)
- 30,651106 eV Confronta Energia di ionizzazione (3ª) di tutti gli elementi →
- Energia di ionizzazione (4ª)
- 54,910189 eV Confronta Energia di ionizzazione (4ª) di tutti gli elementi →
- Energia di ionizzazione (5ª)
- 75,000258 eV Confronta Energia di ionizzazione (5ª) di tutti gli elementi →
- Stati di ossidazione
- −4, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7 Confronta Stati di ossidazione di tutti gli elementi →
- Elettroni di valenza
- 8 Confronta Elettroni di valenza di tutti gli elementi →
- Configurazione elettronica
- [Ar] 4s2 3d6
Termodinamiche
- Punto critico (temperatura)
- 9067 °C
- Calore di fusione
- 0,14313106 eV Confronta Calore di fusione di tutti gli elementi →
- Calore di vaporizzazione
- 3,523864 eV Confronta Calore di vaporizzazione di tutti gli elementi →
- Calore di sublimazione
- 4,306369 eV
- Calore di atomizzazione
- 4,306369 eV
- Entalpia di atomizzazione
- 4,306369 eV
Nucleari
- Protoni
- 26 Confronta Protoni di tutti gli elementi →
- Neutroni
- 30 Confronta Neutroni di tutti gli elementi →
- Isotopi noti
- 32 Confronta Isotopi noti di tutti gli elementi →
- Isotopi stabili
- 4 Confronta Isotopi stabili di tutti gli elementi →
- Isotopo più stabile
- Fe-56
Abbondanza
- Abbondanza (crosta terrestre)
- 5,63e+4 mg/kg Confronta Abbondanza (crosta terrestre) di tutti gli elementi →
- Abbondanza (oceano)
- 0,002 mg/L Confronta Abbondanza (oceano) di tutti gli elementi →
Struttura cristallina
- Costante reticolare a
- 287 pm
Struttura elettronica
- Elettroni per guscio
- 2, 8, 14, 2 Confronta Elettroni per guscio di tutti gli elementi →
Identificativi
- Numero CAS
- 7439-89-6 Confronta Numero CAS di tutti gli elementi →
- Simbolo di termine
- 5D4
- InChI
- InChI=1S/Fe
- Chiave InChI
- XEEYBQQBJWHFJM-UHFFFAOYSA-N
Configurazione elettronica Misurato
Fe: 3d⁶ 4s²[Ar] 3d⁶ 4s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁶ 4s²Modello 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 |
|---|---|---|---|
| 54 Stabile | 53,93960899 ± 0,00000053 | 5,8450% | Stabile |
| 56 Stabile | 55,93493633 ± 0,00000049 | 91,7540% | Stabile |
| 57 Stabile | 56,93539284 ± 0,00000049 | 2,1190% | Stabile |
| 58 Stabile | 57,93327443 ± 0,00000053 | 0,2820% | Stabile |
Fase / Stato
Motivo: 1512,8 °C sotto il punto di fusione (1537,85 °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
Avanzate
Spettri atomici
Sono visualizzati 10 di 26. Ordinamento per carica ionica crescente.
Righe disponibili ?
| Ione | Carica | Righe totali | Probabilità di transizione | Designazioni dei livelli |
|---|---|---|---|---|
| Fe I | 0 | 10031 | 2542 | 9906 |
| Fe II | +1 | 14471 | 7293 | 14471 |
| Fe III | +2 | 4702 | 2361 | 4687 |
| Fe IV | +3 | 258 | 102 | 102 |
| Fe V | +4 | 2310 | 2018 | 2310 |
| Fe VI | +5 | 159 | 159 | 159 |
| Fe VII | +6 | 651 | 651 | 651 |
| Fe VIII | +7 | 92 | 63 | 92 |
| Fe IX | +8 | 56 | 14 | 56 |
| Fe X | +9 | 98 | 64 | 98 |
Livelli disponibili ?
| Ione | Carica | Livelli |
|---|---|---|
| Fe I | 0 | 847 |
| Fe II | +1 | 1028 |
| Fe III | +2 | 596 |
| Fe IV | +3 | 277 |
| Fe V | +4 | 332 |
| Fe VI | +5 | 94 |
| Fe VII | +6 | 210 |
| Fe VIII | +7 | 42 |
| Fe IX | +8 | 35 |
| Fe X | +9 | 65 |
Raggi ionici
Sono visualizzati 10 di 12.
| Carica | Coordinazione | Spin | Raggio |
|---|---|---|---|
| +2 | 4 | high | 63 pm |
| +2 | 4 | high | 64 pm |
| +2 | 6 | low | 61 pm |
| +2 | 6 | high | 78 pm |
| +2 | 8 | high | 92 pm |
| +3 | 4 | high | 49 pm |
| +3 | 5 | N/D | 57.99999999999999 pm |
| +3 | 6 | low | 55.00000000000001 pm |
| +3 | 6 | high | 64.5 pm |
| +3 | 8 | high | 78 pm |
Composti
Isotopi (4)
Common iron is a mixture of four isotopes. Ten other isotopes are known to exist.
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita | Modalità di decadimento | |
|---|---|---|---|---|---|
| 54 Stabile | 53,93960899 ± 0,00000053 | 5,8450% ± 0,0350% | Stabile | stable | |
| 56 Stabile | 55,93493633 ± 0,00000049 | 91,7540% ± 0,0360% | Stabile | stable | |
| 57 Stabile | 56,93539284 ± 0,00000049 | 2,1190% ± 0,0100% | Stabile | stable | |
| 58 Stabile | 57,93327443 ± 0,00000053 | 0,2820% ± 0,0040% | Stabile | stable |
Righe spettrali
Sono visualizzati 50 di 5034. Per impostazione predefinita sono mostrate soltanto le righe spettrali con intensità misurata.
| Lunghezza d'onda (nm) | Intensità | Stadio di ionizzazione | Tipo | Transizione | Accuratezza | Fonte | |
|---|---|---|---|---|---|---|---|
| 387.857282 nm | 1290000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 393.02964 nm | 1150000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 385.637115 nm | 1100000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 389.970707 nm | 1070000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 526.95366 nm | 1020000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 382.444329 nm | 1000000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 392.291129 nm | 1000000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 404.581193 nm | 1000000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 649.49801 nm | 870000 | Fe I | emission | 3d6.4s2 a 3H → 3d7.(4F).4p z 5G* | Misurata | NIST | |
| 406.359365 nm | 830000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 432.57616 nm | 830000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p z 3G* | Misurata | NIST | |
| 440.47498 nm | 810000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p z 5G* | Misurata | NIST | |
| 381.58397 nm | 760000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3D* | Misurata | NIST | |
| 382.588058 nm | 760000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d7.(4F).4p y 5D* | Misurata | NIST | |
| 516.74879 nm | 760000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d6.(5D).4s.4p.(3P*) z 3D* | Misurata | NIST | |
| 389.565597 nm | 740000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 532.80381 nm | 740000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 407.173752 nm | 710000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 392.025748 nm | 650000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 427.17599 nm | 630000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p z 3G* | Misurata | NIST | |
| 430.79017 nm | 630000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p z 3G* | Misurata | NIST | |
| 382.78222 nm | 590000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3D* | Misurata | NIST | |
| 383.422219 nm | 590000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d7.(4F).4p y 5D* | Misurata | NIST | |
| 388.628183 nm | 550000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 640 nm | 490000 | Fe I | emission | 3d6.(5D).4s.4p.(3P*) z 5P* → 3d6.(5D).4s (6D).5s e 5D | Misurata | NIST | |
| 384.10475 nm | 457000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3D* | Misurata | NIST | |
| 522.71889 nm | 437000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d6.(5D).4s.4p.(3P*) z 3D* | Misurata | NIST | |
| 396.925691 nm | 427000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 381.296424 nm | 398000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d6.(5D).4s.4p.(3P*) z 3P* | Misurata | NIST | |
| 537.14891 nm | 389000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 384.04372 nm | 380000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d7.(4F).4p y 5D* | Misurata | NIST | |
| 414.386752 nm | 363000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 390.294512 nm | 302000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3D* | Misurata | NIST | |
| 639.36001 nm | 302000 | Fe I | emission | 3d6.4s2 a 3H → 3d7.(4F).4p z 5G* | Misurata | NIST | |
| 495.75961 nm | 295000 | Fe I | emission | 3d6.(5D).4s.4p.(3P*) z 7F* → 3d6.(5D).4s (6D).5s e 7D | Misurata | NIST | |
| 441.51221 nm | 288000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p z 5G* | Misurata | NIST | |
| 527.03561 nm | 288000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d6.(5D).4s.4p.(3P*) z 3D* | Misurata | NIST | |
| 387.801779 nm | 275000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d7.(4F).4p y 5D* | Misurata | NIST | |
| 642.13496 nm | 257000 | Fe I | emission | 3d6.4s2 a 3P2 → 3d6.(5D).4s.4p.(3P*) z 3P* | Misurata | NIST | |
| 388.704779 nm | 251000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d7.(4F).4p y 5D* | Misurata | NIST | |
| 667.79848 nm | 240000 | Fe I | emission | 3d7.(2G).4s a 3G → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 387.250102 nm | 234000 | Fe I | emission | 3d7.(4F).4s a 5F → 3d7.(4F).4p y 5D* | Misurata | NIST | |
| 390.647918 nm | 234000 | Fe I | emission | 3d6.4s2 a 5D → 3d6.(5D).4s.4p.(3P*) z 5D* | Misurata | NIST | |
| 413.205785 nm | 224000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 426.04736 nm | 224000 | Fe I | emission | 3d6.(5D).4s.4p.(3P*) z 7D* → 3d6.(5D).4s (6D).5s e 7D | Misurata | NIST | |
| 654.62373 nm | 224000 | Fe I | emission | 3d7.(2G).4s a 3G → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 641.16477 nm | 219000 | Fe I | emission | 3d6.(5D).4s.4p.(3P*) z 5P* → 3d6.(5D).4s (6D).5s e 5D | Misurata | NIST | |
| 425.07864 nm | 214000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p z 3G* | Misurata | NIST | |
| 400.524148 nm | 209000 | Fe I | emission | 3d7.(4F).4s a 3F → 3d7.(4F).4p y 3F* | Misurata | NIST | |
| 643.08447 nm | 209000 | Fe I | emission | 3d7.(4P).4s a 5P → 3d7.(4F).4p y 5D* | Misurata | NIST |
Proprietà estese
Raggi covalenti (dati estesi)
- Raggio covalente (Pyykkö)
- 116 pm
- Raggio covalente (Pyykkö, legame doppio)
- 109 pm
- Raggio covalente (Pyykkö, legame triplo)
- 102 pm
- Raggio covalente (Bragg)
- 140 pm
Raggi di van der Waals
- Batsanov
- 205 pm
- Alvarez
- 244 pm
- UFF
- 291,2 pm
- MM3
- 223 pm
Raggi atomici e metallici
- Raggio atomico (Rahm)
- 237 pm
- Raggio metallico (C12)
- 126 pm
Scale di numerazione
- Mendeleev
- 59
- Pettifor
- 61
- Glawe
- 71
Scale di elettronegatività
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 6
- Robles–Bartolotti
- 4
Polarizzabilità e dispersione
- Polarizzabilità dipolare
- 62 a.u.
- Polarizzabilità dipolare (inc.)
- 4 a.u.
- C₆
- 482 Ha·Bohr6
- C₆ (Gould–Bučko)
- 548 Ha·Bohr6
Affinità chimica
- Affinità protonica
- 754 kJ/mol
- Basicità in fase gassosa
- 731,1 kJ/mol
Parametri di Miedema
- Volume molare di Miedema
- 7,09 cm3/mol
- Densità elettronica di Miedema
- 6
Rischio di approvvigionamento ed economia
- Concentrazione della produzione
- 41
- Rischio relativo di approvvigionamento
- 5
- Distribuzione delle riserve
- 21
- Stabilità politica (principale produttore)
- 24
- Stabilità politica (principale detentore di riserve)
- 75
Transizioni di fase e allotropi
| Punto di fusione | 1811,15 K |
| Punto di ebollizione | 3134,15 K |
| Punto critico (temperatura) | 9340,15 K |
Categorie degli stati di ossidazione
Dati di riferimento avanzati
Costanti di schermaggio (7)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 0,619 |
| 2 | p | 3,9112 |
| 2 | s | 7,401 |
| 3 | d | 14,8202 |
| 3 | p | 13,2221 |
| 3 | s | 12,3239 |
| 4 | s | 20,566 |
Dettaglio dei raggi cristallini (12)
| Carica | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 2 | IV | HS | 77 | |
| 2 | IVSQ | HS | 78 | |
| 2 | VI | LS | 75 | estimated, |
| 2 | VI | HS | 92 | from r^3 vs V plots, |
| 2 | VIII | HS | 106 | calculated, |
| 3 | IV | HS | 63 | |
| 3 | V | 72 | ||
| 3 | VI | LS | 69 | from r^3 vs V plots, |
| 3 | VI | HS | 78,5 | from r^3 vs V plots, |
| 3 | VIII | HS | 92 |
Modalità di decadimento degli isotopi (55)
| Isotopo | Modalità | Intensità |
|---|---|---|
| 45 | 2p | 70% |
| 45 | B+ | 30% |
| 45 | B+p | 18,9% |
| 45 | 2p | 7,8% |
| 46 | B+ | 100% |
| 46 | B+p | 78,7% |
| 46 | 2p | — |
| 47 | B+ | 100% |
| 47 | B+p | 88,4% |
| 48 | B+ | 100% |
Fattori di diffusione dei raggi X (504)
| Energia (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1,37852 |
| 10,1617 | — | 1,42961 |
| 10,3261 | — | 1,48259 |
| 10,4931 | — | 1,53754 |
| 10,6628 | — | 1,59453 |
| 10,8353 | — | 1,65362 |
| 11,0106 | — | 1,71491 |
| 11,1886 | — | 1,77847 |
| 11,3696 | — | 1,84438 |
| 11,5535 | — | 1,91274 |
Dati aggiuntivi
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
5.63×104 milligrams per kilogram
Riferimenti (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
2×10-3 milligrams per liter
Riferimenti (1)
Sources
Sources of this element.
Iron is a relatively abundant element in the universe. It is found in the sun and many types of stars in considerable quantity. Its nuclei are very stable. Iron is a principal component of a meteorite class known as siderites and is a minor constituent of the other two meteorite classes. The core of the earth 2150 miles in radius is thought to be largely composed of iron with about 10 percent occluded hydrogen. The metal is the fourth most abundant element, by weight that makes up the crust of the earth.
The most common ore is hematite, which is frequently seen as black sands along beaches and banks of streams.
Riferimenti (1)
- [6] Iron https://periodic.lanl.gov/26.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 Iron.
The element property data was retrieved from publications.