Scandium (Sc)
transition-metalSolid
Masse atomique relative standard
44,955908 uConfiguration électronique
[Ar] 4s2 3d1Point de fusion
1540,85 °CPoint d’ébullition
2835,85 °CMasse volumique
2990 kg/m³États d’oxydation
0, +1, +2, +3Électronégativité (Pauling)
1,36Énergie d’ionisation (1re)
6,56149 eVAnnée de découverte
1879Rayon atomique
160 pmDétails
Scandium is a light transition metal with chemistry dominated by the +3 oxidation state. It is chemically similar to yttrium and the lanthanides, but its small ionic radius gives some distinct coordination behavior. The element is widely dispersed in minerals and rarely occurs in rich, easily worked ores. Its technological importance is concentrated in specialty aluminum alloys, high-intensity lighting, and research materials rather than large-volume metal use.
Scandium is a silver-white metal which develops a slightly yellowish or pinkish cast upon exposure to air. A relatively soft element, scandium resembles yttrium and the rare-earth metals more than it resembles aluminum or titanium.
It is a very light metal and has a much higher melting point than aluminum, making it of interest to designers of spacecraft. Scandium is not attacked by a 1:1 mixture of HNO3 and 48% HF.
Chemically it is one of the alkaline earth elements; it readily forms a white coating of nitride in air, reacts with water, burns with a yellow-red flame.
The name derives from the Latin scandia for Scandinavia, where the mineral was found. It was discovered by the Swedish chemist Lars-Fredrik Nilson in 1879 in an ytterbium sample. In the same year, the Swedish chemist Per Theodore Cleve proved that scandium was Mendeleev's predicted "eka-boron".
Scandium was discovered by Lars Fredrik Nilson, a Swedish chemist, in 1879 while attempting to produce a sample of pure ytterbia from 10 kilograms of the mineral euxenite ((Y, Ca, Er, La, Ce, U, Th)(Nb, Ta, Ti)2O6). Scandium can be obtained from the minerals thortveitite ((Sc, Y)2Si2O7), bazzite (Be3(Sc, Al)2Si6O18) and wiikite, but is usually obtained as a byproduct of refining uranium. Metallic scandium was first produced in 1937 and the first pound (0.45 kilograms) of pure scandium was produced in 1960. Scandium is a soft, light metal that might have applications in the aerospace industry. With a cost of $270 per gram ($122,500 per pound), scandium is too expensive for widespread use.
From the Latin word Scandia, Scandinavia. On the basis of the Periodic System, Mendeleev predicted the existence of ekaboron, which would have an atomic weight between 40 of calcium and 48 of titanium. The element was discovered by Nilson in 1878 in the minerals euxenite and gadolinite, which had not yet been found anywhere except in Scandinavia. By processing 10 kg of euxenite and other residues of rare-earth minerals, Nilson was able to prepare about 2g of highly pure scandium oxide. Later scientists pointed out that Nilson's scandium was identical with Mendeleev's ekaboron.
Pure scandium is a soft, silvery-white metal that tarnishes slowly in air, developing a yellowish or pinkish cast from surface oxidation. It is much less dense than most transition metals and can be cut or worked more readily than refractory metals.
Small additions of scandium strengthen aluminum alloys and improve weldability, especially in high-performance aerospace, sporting, and additive-manufactured components. Scandium iodide, ScI₃, has been used with sodium iodide, NaI, in metal-halide lamps to produce a bright, sunlight-like spectrum. Scandium compounds are also used in research on solid oxide fuel cells, ceramics, catalysts, and optical materials. The radioisotope ⁴⁴Sc is investigated for positron emission tomography, but such medical use depends on isotope production and radiochemical handling rather than bulk scandium metal.
Alloys of scandium and aluminum are used in some kinds of athletic equipment, such as aluminum baseball bats, bicycle frames and lacrosse sticks. It is expected that scandium-aluminum alloys will be important in the manufacture of fuel cells.
Scientists have only studied a few compounds of scandium. About 20 kilograms (44 pounds) of scandium oxide (Sc2O3), also known as scandia, are used each year in the United States in the production of high intensity lights. Scandium iodide (ScI3) is added to mercury vapor lamps so that they will emit light that closely resembles sunlight.
About 20 kg of scandium (as Sc2O3) are used yearly in the U.S. to produce high-intensity lights. The radioactive isotope 46Sc is used as a tracing agent in refinery crackers for crude oil, etc.
Scandium iodide added to mercury vapor lamps produces a highly efficient light source resembling sunlight, which is important for indoor or night-time color TV.
Isotopes in Biology
Radioactive 46Sc is used as a non-absorbed isotopic reference material for determining digestibility, absorption in the gut, and secretion sites for nutrients associated with feed residues in ruminating animals (animals that chew their food repeatedly for an extended period of time) [190] J. K. Miller, W. F. Byrne. J. Nutr.100, 1287 (1970)..
Isotopes in Earth/Planetary Science
The radioactive isotope 46Sc has been used for sediment labeling to determine the transportation of sediments by water flow in rivers, estuaries, harbors, and seas. The half-life of 46Sc is about 84 days and when released into an estuary with similar grain density and grain size, a gamma spectrometer (instrument for measuring the intensity of gamma radiation versus the energy of each photon) can be used to measure the intensities of 46Sc in the sediments and the movement of the sediments can be determined [191] A. Plata-Bedmar. Topical Reports, IAEA Bulletin (1988)., [192] K. Krishnamurthy, S. M. Rao. J. Hydrol.19, 189 (1973)., [193] I. Rehana, K. A. Shahid, S. Husain, D. Muhammad. Appl. Radiat. Isot.51, 115 (1999)..
Isotopes in Industry
46Sc is a beta emitter and has been used as a tracer in oil refinery crackers for crude oil (converting crude oil into gasoline and other lower-molecular weight hydrocarbon fractions). Its beta radiation enables the substance to be tracked as the oil travels [194] J. Guizerix, V. Markovic, P. Airey. Nuclear Techniques for Peaceful Development, IAEA Bulletin (1987).. Due to its easily traceable properties, coastal engineers use 46Sc to develop dredging strategies and to design navigation channels based on silt movement [192] K. Krishnamurthy, S. M. Rao. J. Hydrol.19, 189 (1973)..
Isotopes in Medicine
46Sc is used in isotope-carrying antibodies for bonding with tumor-associated cell surface antigens (substances that causes the production of an antibody when introduced into the body, e.g. toxins, bacteria, and viruses). 46Sc is added to DTPA-derivatized (process by which a compound is chemically changed, producing a new compound that has properties more amenable to a particular analytical method) monoclonal antibodies and has been shown to target tumor cells, specifically in vivo, where it accumulates to high levels in the tumor (Fig. IUPAC.21.1) [195] W. T. Anderson, M. Strand. Cancer Res.45, 2154 (1985)., [196] J. E. Eyles, I. D. Spiers, E. D. Williamson, H. O. Alpar, E. D. Williamson. J. Pharm. Pharmacol.53, 601 (2001)..
Scandium forms predominantly trivalent compounds containing Sc³⁺. Scandium oxide, Sc₂O₃, is a refractory white solid and an important intermediate for preparing other scandium materials. Scandium fluoride, ScF₃, and scandium chloride, ScCl₃, are common salts, with the anhydrous chloride used in some synthetic chemistry. Organoscandium and scandium triflate, Sc(OTf)₃, are useful Lewis acids in research-scale catalysis. Stable lower oxidation states are uncommon under ordinary conditions, although unusual low-valent scandium species can be stabilized in specialized molecular or solid-state environments.
See more information at the Scandium compound page.
Massive scandium metal has low acute toxicity data and is not known to be biologically essential. Finely divided metal dust can present fire or explosion hazards and may irritate the respiratory tract. Soluble scandium salts should be handled as toxicologically incompletely characterized metal compounds. Radioactive scandium isotopes present isotope-specific radiation hazards; ⁴⁶Sc, for example, is a gamma emitter used mainly as a tracer and calibration source.
Little is yet known about the toxicity of scandium; therefore it should be handled with care.
Scandium is a trace constituent of many crustal rocks, commonly substituting for magnesium, iron, aluminum, or rare-earth elements in minerals. It has no major independent biogeochemical cycle and is not a nutrient. Weathering can disperse scandium into soils and sediments, where it tends to remain in mineral phases or adsorb to oxides and clays. Environmental releases are usually associated with mining, ore processing, and industrial handling of scandium-bearing residues.
Scandium is not mined widely as a primary product. Commercial supply is usually recovered as a by-product from selected uranium, titanium, nickel, rare-earth, or bauxite-related processing streams, where scandium is present at low concentrations. The main barrier to wider alloy use is not intrinsic performance but dependable, low-cost supply and purification capacity. Recycling is limited because scandium is used in small amounts and often dispersed in aluminum alloy scrap. Substitution is possible in many applications, but few substitutes reproduce the same strengthening effect in aluminum at such low additions.
Scandium is apparently much more abundant (the 23rd most) in the sun and certain stars than on earth (the 50th most abundant). It is widely distributed on earth, occurring in very minute quantities in over 800 mineral species. The blue color of beryl (aquamarine variety) is said to be due to scandium. It occurs as a principal component in the rare mineral thortveitite, found in Scandinavia and Malagasy. It is also found in the residues remaining after the extraction of tungsten from Zinnwald wolframite, and in wiikite and bazzite.
Most scandium is presently being recovered from thortveitite or is extracted as a by-product from uranium mill tailings. Metallic scandium was first prepared in 1937 by Fischer, Brunger, and Grienelaus who electrolyzed a eutectic melt of potassium, lithium, and scandium chlorides at 700 to 800°C. Tungsten wire and a pool of molten zinc served as the electrodes in a graphite crucible. Pure scandium is now produced by reducing scandium fluoride with calcium metal.
The production of the first pound of 99% pure scandium metal was announced in 1960.
Scandium is a relatively rare odd-Z element in the cosmos. It is produced in stellar nucleosynthesis and supernova-related processes, but in lower abundance than neighboring even-Z elements such as calcium and titanium. In planetary materials it behaves lithophile, concentrating mainly in silicate minerals rather than metallic cores or volatile phases.
- Scandium was discovered after its existence was predicted from a gap below boron in early periodic tables.
- Its name comes from Scandinavia, where scandium-bearing minerals were first studied.
- Aluminum-scandium alloys can retain fine strengthening precipitates after welding better than many conventional aluminum
- Scandium is often grouped with rare-earth elements in processing, although it is not a lanthanide.
- Natural scandium consists almost entirely of the stable isotope ⁴⁵Sc.
- Scandium oxide has a high melting point and is used as a precursor for many scandium chemicals.
Images
Propriétés
Propriétés physiques
- Rayon atomique (empirique)
- 160 pm Comparer : Rayon atomique (empirique) de tous les éléments →
- Rayon covalent
- 170 pm Comparer : Rayon covalent de tous les éléments →
- Rayon de van der Waals
- 211 pm Comparer : Rayon de van der Waals de tous les éléments →
- Rayon métallique
- 144 pm Comparer : Rayon métallique de tous les éléments →
- Masse volumique
- 2990 kg/m³ Comparer : Masse volumique de tous les éléments →
- Volume molaire
- 0,015 L/mol
- Phase aux CNTP
- Solide Comparer : Phase aux CNTP de tous les éléments →
- Point de fusion
- 1540,85 °C Comparer : Point de fusion de tous les éléments →
- Point d’ébullition
- 2835,85 °C Comparer : Point d’ébullition de tous les éléments →
- Conductivité thermique
- 15,8 W/(m·K) Comparer : Conductivité thermique de tous les éléments →
- Capacité thermique massique
- 0,568 J/(g·K) Comparer : Capacité thermique massique de tous les éléments →
- Capacité thermique molaire
- 25,52 J/(mol·K) Comparer : Capacité thermique molaire de tous les éléments →
- Structure cristalline
- Hexagonal compact Comparer : Structure cristalline de tous les éléments →
Propriétés chimiques
- Électronégativité (Pauling)
- 1,36 Comparer : Électronégativité (Pauling) de tous les éléments →
- Électronégativité (Allen)
- 1,19
- Affinité électronique
- 0,188 eV
- Énergie d’ionisation (1re)
- 6,56149 eV Comparer : Énergie d’ionisation (1re) de tous les éléments →
- Énergie d’ionisation (2e)
- 12,799814 eV Comparer : Énergie d’ionisation (2e) de tous les éléments →
- Énergie d’ionisation (3e)
- 24,756924 eV Comparer : Énergie d’ionisation (3e) de tous les éléments →
- Énergie d’ionisation (4e)
- 73,489653 eV Comparer : Énergie d’ionisation (4e) de tous les éléments →
- Énergie d’ionisation (5e)
- 91,950317 eV Comparer : Énergie d’ionisation (5e) de tous les éléments →
- États d’oxydation
- 0, +1, +2, +3 Comparer : États d’oxydation de tous les éléments →
- Électrons de valence
- 3 Comparer : Électrons de valence de tous les éléments →
- Configuration électronique
- [Ar] 4s2 3d1
Propriétés thermodynamiques
- Enthalpie de fusion
- 0,16582889 eV Comparer : Enthalpie de fusion de tous les éléments →
- Enthalpie de vaporisation
- 3,256465 eV Comparer : Enthalpie de vaporisation de tous les éléments →
- Enthalpie de sublimation
- 3,923926 eV
- Enthalpie d’atomisation
- 3,923926 eV
- Enthalpie d’atomisation
- 3,915635 eV
Propriétés nucléaires
- Protons
- 21 Comparer : Protons de tous les éléments →
- Neutrons
- 24 Comparer : Neutrons de tous les éléments →
- Isotopes connus
- 29 Comparer : Isotopes connus de tous les éléments →
- Isotopes stables
- 1 Comparer : Isotopes stables de tous les éléments →
- Isotope le plus stable
- Sc-45
- Année de découverte
- 1879
Abondance
- Abondance (croûte terrestre)
- 22 mg/kg Comparer : Abondance (croûte terrestre) de tous les éléments →
- Abondance (océan)
- 6 × 10−7 mg/L Comparer : Abondance (océan) de tous les éléments →
Structure cristalline
- Paramètre de maille a
- 331 pm
Structure électronique
- Électrons par couche
- 2, 8, 9, 2 Comparer : Électrons par couche de tous les éléments →
Identifiants
- Numéro CAS
- 7440-20-2 Comparer : Numéro CAS de tous les éléments →
- Symbole de terme
- 2D3/2
- InChI
- InChI=1S/Sc
- Clé InChI
- SIXSYDAISGFNSX-UHFFFAOYSA-N
Configuration électronique Mesuré
Sc: 3d¹ 4s²[Ar] 3d¹ 4s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s²Modèle atomique
Les isotopes diffèrent par leur nombre de neutrons, leur masse et leur stabilité — pas par la configuration électronique de l’atome neutre.
Modèle atomique schématique, non à l’échelle.
Empreinte atomique
Spectre d’émission / d’absorption
Distribution isotopique
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie |
|---|---|---|---|
| 45 Stable | 44,95590828 ± 0,00000077 | 100,0000% | Stable |
Phase / État
Explication: 1515,8 °C en dessous du point de fusion (1540,85 °C)
Schématique, non à l’échelle
Points de transition de phase
Énergies de transition
Énergie nécessaire pour faire fondre 1 mol au point de fusion
Énergie nécessaire pour vaporiser 1 mol au point d’ébullition
Énergie nécessaire pour sublimer 1 mol au point de sublimation
Masse volumique
Dans les conditions standard
Dans les conditions standard
Spectres atomiques
Affichage de 10 sur 21. Tri par charge ionique croissante.
Raies répertoriées ?
| Ion | Charge | Nombre total de raies | Probabilités de transition | Désignations des niveaux |
|---|---|---|---|---|
| Sc I | 0 | 2198 | 260 | 1682 |
| Sc II | +1 | 829 | 139 | 829 |
| Sc III | +2 | 133 | 97 | 133 |
| Sc IV | +3 | 408 | 4 | 408 |
| Sc V | +4 | 456 | 16 | 456 |
| Sc VI | +5 | 79 | 12 | 75 |
| Sc VII | +6 | 70 | 37 | 70 |
| Sc VIII | +7 | 75 | 48 | 75 |
| Sc IX | +8 | 42 | 22 | 42 |
| Sc X | +9 | 99 | 29 | 99 |
Niveaux répertoriés ?
| Ion | Charge | Niveaux |
|---|---|---|
| Sc I | 0 | 478 |
| Sc II | +1 | 169 |
| Sc III | +2 | 44 |
| Sc IV | +3 | 129 |
| Sc V | +4 | 119 |
| Sc VI | +5 | 40 |
| Sc VII | +6 | 35 |
| Sc VIII | +7 | 27 |
| Sc IX | +8 | 27 |
| Sc X | +9 | 68 |
Rayons ioniques
| Charge | Coordinence | Spin | Rayon |
|---|---|---|---|
| +3 | 6 | N/D | 74.5 pm |
| +3 | 8 | N/D | 87 pm |
Composés
Isotopes (1)
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie | Mode de désintégration | |
|---|---|---|---|---|---|
| 45 Stable | 44,95590828 ± 0,00000077 | 100,0000% | Stable | stable |
Raies spectrales
Affichage de 50 sur 946. Seules les raies spectrales dont l’intensité a été mesurée sont affichées par défaut.
| Longueur d’onde (nm) | Intensité | Degré d’ionisation | Type | Transition | Précision | Source | |
|---|---|---|---|---|---|---|---|
| 683.5026 nm | 640 | Sc I | emission | 3d2.(3P).4s 2P → 3d2.(3P).4p 2S* | Mesurée | NIST | |
| 681.9491 nm | 485 | Sc I | emission | 3d.4s.(1D).4p 2F* → 3d.4s.(3D).5s 2D | Mesurée | NIST | |
| 673.7872 nm | 465 | Sc I | emission | 3d.4s.(3D).4p 2F* → 3d.4s.(3D).4d 2G | Mesurée | NIST | |
| 673.945 nm | 360 | Sc I | emission | 3d.4s.(3D).4p 2F* → 3d.4s.(3D).4d 2G | Mesurée | NIST | |
| 681.7117 nm | 345 | Sc I | emission | 3d2.(3P).4s 2P → 3d2.(3P).4p 2S* | Mesurée | NIST | |
| 682.9509 nm | 335 | Sc I | emission | 3d.4s.(1D).4p 2F* → 3d.4s.(3D).5s 2D | Mesurée | NIST | |
| 406.8661 nm | 100 | Sc III | emission | 3p6.4d 2D → 3p6.4f 2F* | Mesurée | NIST | |
| 744.9141 nm | 90 | Sc III | emission | 3p6.5s 2S → 3p6.5p 2P* | Mesurée | NIST | |
| 406.121 nm | 80 | Sc III | emission | 3p6.4d 2D → 3p6.4f 2F* | Mesurée | NIST | |
| 625.6013 nm | 80 | Sc III | emission | 3p6.4d 2D → 3p6.5p 2P* | Mesurée | NIST | |
| 503.2072 nm | 60 | Sc III | emission | 3p6.5p 2P* → 3p6.5d 2D | Mesurée | NIST | |
| 630.7603 nm | 60 | Sc III | emission | 3p6.4d 2D → 3p6.5p 2P* | Mesurée | NIST | |
| 499.2886 nm | 50 | Sc III | emission | 3p6.5p 2P* → 3p6.5d 2D | Mesurée | NIST | |
| 652.5571 nm | 40 | Sc I | emission | 3d.4s.(3D).4p 2D* → 3d.4s.(3D).4d 2D | Mesurée | NIST | |
| 671.4599 nm | 40 | Sc I | emission | 3d.4s.(3D).4p 2D* → 3d.4s.(3D).4d 4D | Mesurée | NIST | |
| 655.7842 nm | 35 | Sc I | emission | 3d.4s.(1D).4p 2F* → 3d3 2D2 | Mesurée | NIST | |
| 688.5119 nm | 27 | Sc I | emission | 3d2.(3F).4p 4F* → 3d2.(3F).4d 4G | Mesurée | NIST | |
| 716.9083 nm | 27 | Sc I | emission | 3d.4s.(3D).4p 2D* → 3d.4s.(3D).4d 2F | Mesurée | NIST | |
| 688.1012 nm | 26 | Sc I | emission | 3d2.(3F).4p 4F* → 3d2.(3F).4d 4G | Mesurée | NIST | |
| 662.0207 nm | 21 | Sc I | emission | 3d.4s.(3D).4p 2F* → 3d3 2F | Mesurée | NIST | |
| 713.8107 nm | 19 | Sc I | emission | 3d.4s.(3D).4p 2D* → 3d.4s.(3D).4d 2F | Mesurée | NIST | |
| 467.0407 nm | 18 | Sc II | emission | 3p6.3d2 1D → 3p6.3d.4p 1F* | Mesurée | NIST | |
| 673.0754 nm | 18 | Sc I | emission | 3d2.(3F).4p 4D* → 4P | Mesurée | NIST | |
| 687.7343 nm | 18 | Sc I | emission | 3d2.(3F).4p 4F* → 3d2.(3F).4d 4G | Mesurée | NIST | |
| 431.4083 nm | 17 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3D* | Mesurée | NIST | |
| 503.1021 nm | 17 | Sc II | emission | 3p6.3d2 1D → 3p6.3d.4p 1P* | Mesurée | NIST | |
| 680.4611 nm | 17 | Sc I | emission | 3d2.(3F).4p 4F* → 3d2.(3F).4d 4D | Mesurée | NIST | |
| 437.4457 nm | 16 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3F* | Mesurée | NIST | |
| 523.9813 nm | 16 | Sc II | emission | 3p6.4s2 1S → 3p6.3d.4p 1P* | Mesurée | NIST | |
| 552.679 nm | 16 | Sc II | emission | 3p6.3d2 1G → 3p6.3d.4p 1F* | Mesurée | NIST | |
| 430.5714 nm | 15 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3D* | Mesurée | NIST | |
| 432.0732 nm | 15 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3D* | Mesurée | NIST | |
| 478.0863 nm | 15 | Sc III | emission | 3p6.5p 2P* → 3p6.6s 2S | Mesurée | NIST | |
| 565.7896 nm | 15 | Sc II | emission | 3p6.3d2 3P → 3p6.3d.4p 3P* | Mesurée | NIST | |
| 624.5637 nm | 15 | Sc II | emission | 3p6.3d2 3P → 3p6.3d.4p 3D* | Mesurée | NIST | |
| 577.1538 nm | 14 | Sc IV | emission | 3s2.3p5.(2P*<3/2>).5s 2[3/2]* → 3s2.3p5.(2P*<3/2>).5p 2[5/2] | Mesurée | NIST | |
| 637.0486 nm | 14 | Sc II | emission | 3p6.3d.4d 1F → 3p6.3d.4f 1G* | Mesurée | NIST | |
| 660.4601 nm | 14 | Sc II | emission | 3p6.3d2 1D → 3p6.3d.4p 1D* | Mesurée | NIST | |
| 680.3677 nm | 14 | Sc I | emission | 3d.4s.(3D).4p 2F* → 3d.4s.(3D).4d 2G | Mesurée | NIST | |
| 725.7589 nm | 14 | Sc I | emission | 3d2.(3F).4p 4F* → 3d.(2D).4p2.(3P) 4F | Mesurée | NIST | |
| 401.4484 nm | 13 | Sc II | emission | 3p6.3d.4s 1D → 3p6.3d.4p 3F* | Mesurée | NIST | |
| 429.4767 nm | 13 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3D* | Mesurée | NIST | |
| 432.4996 nm | 13 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3D* | Mesurée | NIST | |
| 564.1001 nm | 13 | Sc II | emission | 3p6.3d2 3P → 3p6.3d.4p 3P* | Mesurée | NIST | |
| 565.8361 nm | 13 | Sc II | emission | 3p6.3d2 3P → 3p6.3d.4p 3P* | Mesurée | NIST | |
| 566.9042 nm | 13 | Sc II | emission | 3p6.3d2 3P → 3p6.3d.4p 3P* | Mesurée | NIST | |
| 687.4193 nm | 13 | Sc I | emission | 3d2.(3F).4p 4F* → 3d2.(3F).4d 4G | Mesurée | NIST | |
| 385.9595 nm | 12 | Sc II | emission | 3p6.3d.4p 1F* → 3p6.3d.5s 1D | Mesurée | NIST | |
| 424.6822 nm | 12 | Sc II | emission | 3p6.3d.4s 1D → 3p6.3d.4p 1D* | Mesurée | NIST | |
| 435.4598 nm | 12 | Sc II | emission | 3p6.3d2 3F → 3p6.3d.4p 3F* | Mesurée | NIST |
Propriétés étendues
Rayons covalents (données étendues)
- Rayon covalent (Pyykkö)
- 148 pm
- Rayon covalent (Pyykkö, liaison double)
- 116 pm
- Rayon covalent (Pyykkö, liaison triple)
- 114 pm
Rayons de van der Waals
- Batsanov
- 230 pm
- Alvarez
- 258 pm
- UFF
- 329,5 pm
- MM3
- 261 pm
Rayons atomiques et métalliques
- Rayon atomique (Rahm)
- 263 pm
- Rayon métallique (C12)
- 162 pm
Échelles de numérotation
- Mendeleev
- 11
- Pettifor
- 20
- Glawe
- 48
Échelles d’électronégativité
- Ghosh
- 0
- Miedema
- 3
- Gunnarsson–Lundqvist
- 4
- Robles–Bartolotti
- 3
Polarisabilité et dispersion
- Polarisabilité dipolaire
- 97 a.u.
- Polarisabilité dipolaire (incertitude)
- 10 a.u.
- C₆
- 1383 Ha·Bohr6
- C₆ (Gould–Bučko)
- 1570 Ha·Bohr6
Affinité chimique
- Affinité protonique
- 914 kJ/mol
- Basicité en phase gazeuse
- 892 kJ/mol
Paramètres de Miedema
- Volume molaire de Miedema
- 15,03 cm3/mol
- Densité électronique de Miedema
- 2
Risque d’approvisionnement et économie
- Concentration de la production
- 97
- Risque relatif d’approvisionnement
- 10
- Répartition des réserves
- 50
- Stabilité politique (principal producteur)
- 24
- Stabilité politique (principal détenteur de réserves)
- 24
Transitions de phase et allotropes
| Point de fusion | 1814,15 K |
| Point d’ébullition | 3109,15 K |
Catégories d’états d’oxydation
Données de référence avancées
Constantes d’écran (7)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 0,5434 |
| 2 | p | 3,9454 |
| 2 | s | 6,4264 |
| 3 | d | 13,8801 |
| 3 | p | 11,5938 |
| 3 | s | 10,6602 |
| 4 | s | 16,3676 |
Détail des rayons cristallins (2)
| Charge | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 3 | VI | 88,5 | from r^3 vs V plots, | |
| 3 | VIII | 101 | from r^3 vs V plots, |
Modes de désintégration des isotopes (52)
| Isotope | Mode | Intensité |
|---|---|---|
| 35 | p | — |
| 36 | p | — |
| 37 | p | — |
| 38 | p | — |
| 39 | p | 100% |
| 40 | B+ | 100% |
| 40 | B+p | 0,4% |
| 40 | B+A | 0% |
| 41 | B+ | 100% |
| 42 | B+ | 100% |
Facteurs de diffusion des rayons X (598)
| Énergie (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1,06978 |
| 10,1617 | — | 1,07987 |
| 10,3261 | — | 1,09005 |
| 10,4931 | — | 1,10033 |
| 10,6628 | — | 1,11071 |
| 10,8353 | — | 1,12118 |
| 11,0105 | — | 1,13176 |
| 11,1886 | — | 1,14243 |
| 11,3696 | — | 1,15321 |
| 11,5535 | — | 1,16408 |
Données complémentaires
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
2.2×101 milligrams per kilogram
Références (1)
- [5] Scandium https://education.jlab.org/itselemental/ele021.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
6×10-7 milligrams per liter
Références (1)
- [5] Scandium https://education.jlab.org/itselemental/ele021.html
Sources
Sources of this element.
Scandium is apparently much more abundant (the 23rd most) in the sun and certain stars than on earth (the 50th most abundant). It is widely distributed on earth, occurring in very minute quantities in over 800 mineral species. The blue color of beryl (aquamarine variety) is said to be due to scandium. It occurs as a principal component in the rare mineral thortveitite, found in Scandinavia and Malagasy. It is also found in the residues remaining after the extraction of tungsten from Zinnwald wolframite, and in wiikite and bazzite.
Most scandium is presently being recovered from thortveitite or is extracted as a by-product from uranium mill tailings. Metallic scandium was first prepared in 1937 by Fischer, Brunger, and Grienelaus who electrolyzed a eutectic melt of potassium, lithium, and scandium chlorides at 700 to 800°C. Tungsten wire and a pool of molten zinc served as the electrodes in a graphite crucible. Pure scandium is now produced by reducing scandium fluoride with calcium metal.
The production of the first pound of 99% pure scandium metal was announced in 1960.
Références (1)
- [6] Scandium https://periodic.lanl.gov/21.shtml
Références
(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 Scandium.
The element property data was retrieved from publications.