Scandium

"Element 21" redirects here. For the golf company, see Element 21 (company).

Scandium is a chemical element with the symbol Sc and atomic number 21. It is a silvery-white metallic d-block element. Historically, it has been classified as a rare-earth element,^[7] together with yttrium and the lanthanides. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia.^[8]

Scandium, ₂₁Sc

Scandium
Pronunciation	/ˈskændiəm/ ​(SKAN-dee-əm)
Appearance	silvery white
Standard atomic weight Ar°(Sc)
	44.955907±0.000004 44.956±0.001 (abridged)^[1]
Scandium in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson – ↑ Sc ↓ Y calcium ← scandium → titanium
Atomic number (Z)	21
Group	group 3
Period	period 4
Block	d-block
Electron configuration	[Ar] 3d^1 4s^2
Electrons per shell	2, 8, 9, 2
Physical properties
Phase at STP	solid
Melting point	1814 K ​(1541 °C, ​2806 °F)
Boiling point	3109 K ​(2836 °C, ​5136 °F)
Density (near r.t.)	2.985 g/cm^3
when liquid (at m.p.)	2.80 g/cm^3
Heat of fusion	14.1 kJ/mol
Heat of vaporization	332.7 kJ/mol
Molar heat capacity	25.52 J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1645 1804 (2006) (2266) (2613) (3101)
Atomic properties
Oxidation states	0,^[2] +1,^[3] +2,^[4] +3 (an amphoteric oxide)
Electronegativity	Pauling scale: 1.36
Ionization energies	1st: 633.1 kJ/mol 2nd: 1235.0 kJ/mol 3rd: 2388.6 kJ/mol (more)
Atomic radius	empirical: 162 pm
Covalent radius	170±7 pm
Van der Waals radius	211 pm
Spectral lines of scandium
Other properties
Natural occurrence	primordial
Crystal structure	​hexagonal close-packed (hcp)
Thermal expansion	α, poly: 10.2 µm/(m⋅K) (at r.t.)
Thermal conductivity	15.8 W/(m⋅K)
Electrical resistivity	α, poly: 562 nΩ⋅m (at r.t., calculated)
Magnetic ordering	paramagnetic
Molar magnetic susceptibility	+315.0×10^−6 cm^3/mol (292 K)^[5]
Young's modulus	74.4 GPa
Shear modulus	29.1 GPa
Bulk modulus	56.6 GPa
Poisson ratio	0.279
Brinell hardness	736–1200 MPa
CAS Number	7440-20-2
History
Naming	after Scandinavia
Prediction	Dmitri Mendeleev (1871)
Discovery and first isolation	Lars Fredrik Nilson (1879)
Isotopes of scandium v e
Main isotopes^[6] Decay abun­dance half-life (t1/2) mode pro­duct ^44m2Sc synth 58.61 h IT ^44Sc γ ^44Sc ε ^44Ca ^45Sc 100% stable ^46Sc synth 83.79 d β^− ^46Ti γ – ^47Sc synth 80.38 h β^− ^47Ti γ – ^48Sc synth 43.67 h β^− ^48Ti γ –
Category: Scandium view talk edit | references

Scandium is present in most of the deposits of rare-earth and uranium compounds, but it is extracted from these ores in only a few mines worldwide. Because of the low availability and difficulties in the preparation of metallic scandium, which was first done in 1937, applications for scandium were not developed until the 1970s, when the positive effects of scandium on aluminium alloys were discovered. To this day, its use in such alloys remains its only major application. The global trade of scandium oxide is 15–20 tonnes per year.^[9]

The properties of scandium compounds are intermediate between those of aluminium and yttrium. A diagonal relationship exists between the behavior of magnesium and scandium, just as there is between beryllium and aluminium. In the chemical compounds of the elements in group 3, the predominant oxidation state is +3.

Properties

Chemical characteristics

Scandium is a soft metal with a silvery appearance. It develops a slightly yellowish or pinkish cast when oxidized by air. It is susceptible to weathering and dissolves slowly in most dilute acids. It does not react with a 1:1 mixture of nitric acid (HNO₃) and 48.0% hydrofluoric acid (HF), possibly due to the formation of an impermeable passive layer. Scandium turnings ignite in the air with a brilliant yellow flame to form scandium oxide.^[10]

Isotopes

Main article: Isotopes of scandium

In nature, scandium is found exclusively as the isotope ⁴⁵Sc, which has a nuclear spin of 7/2; this is its only stable isotope. Twenty-five radioisotopes have been characterized with the most stable being ⁴⁶Sc, which has a half-life of 83.8 days; ⁴⁷Sc, 3.35 days; the positron emitter ⁴⁴Sc, 4 hours; and ⁴⁸Sc, 43.7 hours. All of the remaining radioactive isotopes have half-lives less than 4 hours, and the majority of these have half-lives less than 2 minutes. This element also has five nuclear isomers, with the most stable being ^44m2Sc (t_1/2 = 58.6 h).^[11]

The known isotopes of scandium range from ³⁶Sc to ⁶⁰Sc. The primary decay mode at masses lower than the only stable isotope, ⁴⁵Sc, is electron capture, and the primary mode at masses above it is beta emission. The primary decay products at atomic weights below ⁴⁵Sc are calcium isotopes and the primary products from higher atomic weights are titanium isotopes.^[11]

Occurrence

In Earth's crust, scandium is not rare. Estimates vary from 18 to 25 ppm, which is comparable to the abundance of cobalt (20–30 ppm). Scandium is only the 50th most common element on Earth (35th most abundant in the crust), but it is the 23rd most common element in the Sun.^[12] However, scandium is distributed sparsely and occurs in trace amounts in many minerals.^[13] Rare minerals from Scandinavia^[14] and Madagascar^[15] such as thortveitite, euxenite, and gadolinite are the only known concentrated sources of this element. Thortveitite can contain up to 45% of scandium in the form of scandium oxide.^[14]

The stable form of scandium is created in supernovas via the r-process.^[16] Also, scandium is created by cosmic ray spallation of the more abundant iron nuclei.

• ²⁸Si + 17n → ⁴⁵Sc (r-process)
• ⁵⁶Fe + p → ⁴⁵Sc + ¹¹C + n (cosmic ray spallation)

Production

The world production of scandium is in the order of 15–20 tonnes per year, in the form of scandium oxide. The demand is about 50% higher^{[citation needed]}, and both the production and demand keep increasing. In 2003, only three mines produced scandium: the uranium and iron mines in Zhovti Vody in Ukraine, the rare-earth mines in Bayan Obo, China, and the apatite mines in the Kola Peninsula, Russia.^{[citation needed]} Since then, many other countries have built scandium-producing facilities, including 5 tonnes/year (7.5 tonnes/year Sc₂O₃) by Nickel Asia Corporation and Sumitomo Metal Mining in the Philippines.^[17][18] In the United States, NioCorp Development hopes^[when?] to raise $1 billion^[19] toward opening a niobium mine at its Elk Creek site in southeast Nebraska,^[20] which may be able to produce as much as 95 tonnes of scandium oxide annually.^[21] In each case, scandium is a byproduct of the extraction of other elements and is sold as scandium oxide.^[22][23][24]

To produce metallic scandium, the oxide is converted to scandium fluoride and then reduced with metallic calcium.^[25]

• Sc₂O₃ + 6HF → 2ScF₃ + 3H₂O
• 2ScF₃ + 3Ca → 3CaF₂ + 2Sc

Madagascar and the Iveland-Evje region in Norway have the only deposits of minerals with high scandium content, thortveitite (Sc,Y)₂(Si₂O₇), but these are not being exploited.^[23] The mineral kolbeckite ScPO₄·2H₂O has a very high scandium content but is not available in any larger deposits.^[23]

The absence of reliable, secure, stable, long-term production has limited the commercial applications of scandium. Despite this low level of use, scandium offers significant benefits. Particularly promising is the strengthening of aluminium alloys with as little as 0.5% scandium.^[26] Scandium-stabilized zirconia enjoys a growing market demand for use as a high-efficiency electrolyte in solid oxide fuel cells.

The USGS reports that, from 2015 to 2019 in the US, the price of small quantities of scandium ingot has been $107 to $134 per gram, and that of scandium oxide $4 to $5 per gram.^[27]

Compounds

See also the categories Scandium compounds and Scandium minerals

Scandium chemistry is almost completely dominated by the trivalent ion, Sc³⁺. The radii of M³⁺ ions in the table below indicate that the chemical properties of scandium ions have more in common with yttrium ions than with aluminium ions. In part because of this similarity, scandium is often classified as a lanthanide-like element.^[28]

Ionic radii (pm)

Al	Sc	Y	La	Lu
53.5	74.5	90.0	103.2	86.1

Oxides and hydroxides

The oxide Sc
₂O
₃ and the hydroxide Sc(OH)
₃ are amphoteric:^[29]

Sc(OH)
₃ + 3 OH⁻
→ [Sc(OH)
₆]³⁻
(scandate ion)

Sc(OH)
₃ + 3 H⁺
+ 3 H
₂O → [Sc(H
₂O)
₆]³⁺

α- and γ-ScOOH are isostructural with their aluminium hydroxide oxide counterparts.^[30] Solutions of Sc³⁺
in water are acidic due to hydrolysis.

Halides and pseudohalides

The halides ScX₃, where X= Cl, Br, or I, are very soluble in water, but ScF₃ is insoluble. In all four halides, the scandium is 6-coordinated. The halides are Lewis acids; for example, ScF₃ dissolves in a solution containing excess fluoride ion to form [ScF₆]³⁻. The coordination number 6 is typical for Sc(III). In the larger Y³⁺ and La³⁺ ions, coordination numbers of 8 and 9 are common. Scandium triflate is sometimes used as a Lewis acid catalyst in organic chemistry.^[31]

Organic derivatives

Main article: Organoscandium chemistry

Scandium forms a series of organometallic compounds with cyclopentadienyl ligands (Cp), similar to the behavior of the lanthanides. One example is the chlorine-bridged dimer, [ScCp₂Cl]₂ and related derivatives of pentamethylcyclopentadienyl ligands.^[32]

Uncommon oxidation states

Compounds that feature scandium in oxidation states other than +3 are rare but well characterized. The blue-black compound CsScCl₃ is one of the simplest. This material adopts a sheet-like structure that exhibits extensive bonding between the scandium(II) centers.^[33] Scandium hydride is not well understood, although it appears not to be a saline hydride of Sc(II).^[4] As is observed for most elements, a diatomic scandium hydride has been observed spectroscopically at high temperatures in the gas phase.^[3] Scandium borides and carbides are non-stoichiometric, as is typical for neighboring elements.^[34]

Lower oxidation states (+2, +1, 0) have also been observed in organoscandium compounds.^{[35][36][37][38]}

History

Lars Fredrik Nilson and his team detected this element in the minerals euxenite and gadolinite in 1879. Nilson prepared 2 grams of scandium oxide of high purity.^[39][40] He named the element scandium, from the Latin Scandia meaning "Scandinavia". Nilson was apparently unaware of Mendeleev's prediction, but Per Teodor Cleve recognized the correspondence and notified Mendeleev.^[41][42]

Metallic scandium was produced for the first time in 1937 by electrolysis of a eutectic mixture of potassium, lithium, and scandium chlorides, at 700–800 °C.^[43] The first pound of 99% pure scandium metal was produced in 1960. Production of aluminium alloys began in 1971, following a US patent.^[44] Aluminium-scandium alloys were also developed in the USSR.^[45]

Laser crystals of gadolinium-scandium-gallium garnet (GSGG) were used in strategic defense applications developed for the Strategic Defense Initiative (SDI) in the 1980s and 1990s.^[46][47]

Red giant stars near the Galactic Center

In early 2018, evidence was gathered from spectrometer data of significant scandium, vanadium, and yttrium abundances in red giant stars in the Nuclear Star Cluster (NSC) in the Galactic Center. Further research showed that this was an illusion caused by the relatively low temperature (below 3,500 K) of these stars masking the abundance signals, and that this phenomenon was observable in other red giants.^[48]

Applications

Further information: Aluminium–scandium alloys

 

Parts of the MiG-29 are made from Al-Sc alloy.^[49]

The addition of scandium to aluminium limits the grain growth in the heat zone of welded aluminium components. This has two beneficial effects: the precipitated Al₃Sc forms smaller crystals than in other aluminium alloys,^[49] and the volume of precipitate-free zones at the grain boundaries of age-hardening aluminium alloys is reduced.^[49] The Al₃Sc precipitate is a coherent precipitate that strengthens the aluminum matrix by applying elastic strain fields that inhibit dislocation movement (i.e., plastic deformation). Al₃Sc has an equilibrium L1₂ superlattice structure exclusive to this system.^[50] A fine dispersion of nano scale precipitate can be achieved via heat treatment that can also strengthen the alloys through order hardening.^[51] Recent developments include the additions of transition metals such as Zr and rare earth metals like Er produce shells surrounding the spherical Al₃Sc precipitate that reduce coarsening.^[52] These shells are dictated by the diffusivity of the alloying element and lower the cost of the alloy due to less Sc being substituted in part by Zr while maintaining stability and less Sc being needed to form the precipitate.^[53] These have made Al₃Sc somewhat competitive with titanium alloys along with a wide array of applications. However, titanium alloys, which are similar in lightness and strength, are cheaper and much more widely used.^[54]

The alloy Al₂₀Li₂₀Mg₁₀Sc₂₀Ti₃₀ is as strong as titanium, light as aluminium, and hard as some ceramics.^[55]

The main application of scandium by weight is in aluminium-scandium alloys for minor aerospace industry components. These alloys contain between 0.1% and 0.5% of scandium. They were used in Russian military aircraft, specifically the Mikoyan-Gurevich MiG-21 and MiG-29.^[49]

Some items of sports equipment, which rely on lightweight high-performance materials, have been made with scandium-aluminium alloys, including baseball bats,^[56] tent poles and bicycle frames and components.^[57] Lacrosse sticks are also made with scandium. The American firearm manufacturing company Smith & Wesson produces semi-automatic pistols and revolvers with frames of scandium alloy and cylinders of titanium or carbon steel.^[58][59]

Dentists use erbium-chromium-doped yttrium-scandium-gallium garnet (Er,Cr:YSGG) lasers for cavity preparation and in endodontics.^[60]

The first scandium-based metal-halide lamps were patented by General Electric and made in North America, although they are now produced in all major industrialized countries. Approximately 20 kg of scandium (as Sc₂O₃) is used annually in the United States for high-intensity discharge lamps.^[61] One type of metal-halide lamp, similar to the mercury-vapor lamp, is made from scandium triiodide and sodium iodide. This lamp is a white-light source with high color rendering index that sufficiently resembles sunlight to allow good color-reproduction with TV cameras.^[62] About 80 kg of scandium is used in metal-halide lamps/light bulbs globally per year.^{[citation needed][63]}

The radioactive isotope ⁴⁶Sc is used in oil refineries as a tracing agent.^[61] Scandium triflate is a catalytic Lewis acid used in organic chemistry.^[64]

Health and safety

Elemental scandium is considered non-toxic, though extensive animal testing of scandium compounds has not been done.^[65] The median lethal dose (LD₅₀) levels for scandium chloride for rats have been determined as 755 mg/kg for intraperitoneal and 4 g/kg for oral administration.^[66] In the light of these results, compounds of scandium should be handled as compounds of moderate toxicity. Scandium appears to be handled by the body in a manner similar to gallium, with similar hazards involving its poorly soluble hydroxide.^[67]

See also

• Rare-earth element

References

1. "Standard Atomic Weights: Scandium". CIAAW. 2021.
2. Cloke, F. Geoffrey N.; Khan, Karl & Perutz, Robin N. (1991). "η-Arene complexes of scandium(0) and scandium(II)". J. Chem. Soc., Chem. Commun. (19): 1372–1373. doi:10.1039/C39910001372.
3. Smith, R. E. (1973). "Diatomic Hydride and Deuteride Spectra of the Second Row Transition Metals". Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences. 332 (1588): 113–127. Bibcode:1973RSPSA.332..113S. doi:10.1098/rspa.1973.0015. S2CID 96908213.
4. McGuire, Joseph C.; Kempter, Charles P. (1960). "Preparation and Properties of Scandium Dihydride". Journal of Chemical Physics. 33 (5): 1584–1585. Bibcode:1960JChPh..33.1584M. doi:10.1063/1.1731452.
5. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
6. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
7. (PDF). Archived from the original (PDF) on 2008-05-27.
8. Samson, Iain M.; Chassé, Mathieu (2016), "Scandium", in White, William M. (ed.), Encyclopedia of Geochemistry: A Comprehensive Reference Source on the Chemistry of the Earth, Cham: Springer International Publishing, pp. 1–5, doi:10.1007/978-3-319-39193-9_281-1, ISBN 978-3-319-39193-9, retrieved 2023-02-01
9. "Mineral Commodity Summaries 2020" (PDF). US Geological Survey Mineral Commodities Summary 2020. US Geological Survey. Retrieved 10 February 2020.
10. "Scandium." Los Alamos National Laboratory. Retrieved 2013-07-17.
11. Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003). "The NUBASE Evaluation of Nuclear and Decay Properties". Nuclear Physics A. 729 (1): 3–128. Bibcode:2003NuPhA.729....3A. CiteSeerX 10.1.1.692.8504. doi:10.1016/j.nuclphysa.2003.11.001.
12. Lide, David R. (2004). CRC Handbook of Chemistry and Physics. Boca Raton: CRC Press. pp. 4–28. ISBN 978-0-8493-0485-9.
13. Bernhard, F. (2001). "Scandium mineralization associated with hydrothermal lazurite-quartz veins in the Lower Austroalpie Grobgneis complex, East Alps, Austria". Mineral Deposits in the Beginning of the 21st Century. Lisse: Balkema. ISBN 978-90-265-1846-1.
14. Kristiansen, Roy (2003). "Scandium – Mineraler I Norge" (PDF). Stein (in Norwegian): 14–23.
15. von Knorring, O.; Condliffe, E. (1987). "Mineralized pegmatites in Africa". Geological Journal. 22: 253. doi:10.1002/gj.3350220619.
16. Cameron, A.G.W. (June 1957). "Stellar Evolution, Nuclear Astrophysics, and Nucleogenesis" (PDF). CRL-41.
17. "Establishment of Scandium Recovery Operations" (PDF). Retrieved 2018-10-26.
18. Iwamoto, Fumio. "Commercial Scandium Oxide Production by Sumitomo Metal Mining Co. Ltd". TMS. Retrieved 2018-10-26.
19. "NioCorp Announces Final Closing of Non-Brokered Private Placement for Aggregate Gross Proceeds of C$1.77 Million" (Press release). Retrieved 2019-05-18.
20. "Long-discussed niobium mine in southeast Nebraska is ready to move forward, if it gathers $1 billion in financing ". Retrieved 2019-05-18.
21. NioCorp Superalloy Materials The Elk Creek Superalloy Materials Project (PDF), retrieved 2019-05-18
22. Deschamps, Y. (PDF). mineralinfo.com. Archived from the original (PDF) on 2012-03-24. Retrieved 2008-10-21.
23. "Mineral Commodity Summaries 2015: Scandium" (PDF). United States Geological Survey.
24. Scandium. USGS.
25. Fujii, Satoshi; Tsubaki, Shuntaro; Inazu, Naomi; Suzuki, Eiichi; Wada, Yuji (2017-09-27). "Smelting of Scandium by Microwave Irradiation". Materials. 10 (10): 1138. doi:10.3390/ma10101138. ISSN 1996-1944. PMC 5666944. PMID 28953241.
26. Zakharov, V. V. (2014-09-01). "Combined Alloying of Aluminum Alloys with Scandium and Zirconium". Metal Science and Heat Treatment. 56 (5): 281–286. doi:10.1007/s11041-014-9746-5. ISSN 1573-8973. S2CID 135839152.
27. "Mineral Commodity Summaries". USGS. Retrieved 2020-09-13.
28. Horovitz, Chaim T. (2012-12-06). Biochemistry of Scandium and Yttrium, Part 1: Physical and Chemical Fundamentals. Springer Science & Business Media. ISBN 978-1-4615-4313-8.
29. Cotton, Simon (2006). Lanthanide and actinide chemistry. John Wiley and Sons. pp. 108–. ISBN 978-0-470-01006-8. Retrieved 2011-06-23.
30. Christensen, A. Nørlund; Stig Jorgo Jensen (1967). "Hydrothermal Preparation of α-ScOOH and of γ-ScOOH. Crystal Structure of α-ScOOH". Acta Chemica Scandinavica. 21: 1121–126. doi:10.3891/acta.chem.scand.21-0121.
31. Deborah Longbottom (1999). "SYNLETT Spotlight 12: Scandium Triflate". Synlett. 1999 (12): 2023. doi:10.1055/s-1999-5997.
32. Shapiro, Pamela J.; et al. (1994). "Model Ziegler-Natta α-Olefin Polymerization Catalysts Derived from [{(η⁵-C₅Me₄)SiMe₂(η¹-NCMe₃)}(PMe₃)Sc(μ₂-H)]₂ and [{(η⁵C₅Me₄)SiMe₂(η¹NCMe₃)}Sc(μ¹CH₂CH₂CH₃)]₂. Synthesis, Structures and Kinetic and Equilibrium Investigations of the Catalytically active Species in Solution". Journal of the American Chemical Society. 116 (11): 4623. doi:10.1021/ja00090a011.
33. Corbett, J. D. (1981). "Extended metal-metal bonding in halides of the early transition metals". Accounts of Chemical Research. 14 (8): 239–246. doi:10.1021/ar00068a003.
34. Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
35. Polly L. Arnold; F. Geoffrey; N. Cloke; Peter B. Hitchcock & John F. Nixon (1996). "The First Example of a Formal Scandium(I) Complex: Synthesis and Molecular Structure of a 22-Electron Scandium Triple Decker Incorporating the Novel 1,3,5-Triphosphabenzene Ring". Journal of the American Chemical Society. 118 (32): 7630–7631. doi:10.1021/ja961253o.
36. F. Geoffrey N. Cloke; Karl Khan & Robin N. Perutz (1991). "η-Arene complexes of scandium(0) and scandium(II)". Journal of the Chemical Society, Chemical Communications (19): 1372–1373. doi:10.1039/C39910001372.
37. Ana Mirela Neculai; Dante Neculai; Herbert W. Roesky; Jörg Magull; Marc Baldus; et al. (2002). "Stabilization of a Diamagnetic Sc^IBr Molecule in a Sandwich-Like Structure". Organometallics. 21 (13): 2590–2592. doi:10.1021/om020090b.
38. Polly L. Arnold; F. Geoffrey; N. Cloke & John F. Nixon (1998). "The first stable scandocene: synthesis and characterisation of bis(η-2,4,5-tri-tert-butyl-1,3-diphosphacyclopentadienyl)scandium(II)". Chemical Communications (7): 797–798. doi:10.1039/A800089A.
39. Nilson, Lars Fredrik (1879). "Sur l'ytterbine, terre nouvelle de M. Marignac". Comptes Rendus (in French). 88: 642–647.
40. Nilson, Lars Fredrik (1879). "Ueber Scandium, ein neues Erdmetall". Berichte der deutschen chemischen Gesellschaft (in German). 12 (1): 554–557. doi:10.1002/cber.187901201157.
41. Cleve, Per Teodor (1879). "Sur le scandium". Comptes Rendus (in French). 89: 419–422.
42. Weeks, Mary Elvira (1956). The discovery of the elements (6th ed.). Easton, PA: Journal of Chemical Education.
43. Fischer, Werner; Brünger, Karl; Grieneisen, Hans (1937). "Über das metallische Scandium". Zeitschrift für anorganische und allgemeine Chemie (in German). 231 (1–2): 54–62. doi:10.1002/zaac.19372310107.
44. Burrell, A. Willey Lower "Aluminum scandium alloy" U.S. Patent 3,619,181 issued on November 9, 1971.
45. Zakharov, V. V. (2003). "Effect of Scandium on the Structure and Properties of Aluminum Alloys". Metal Science and Heat Treatment. 45 (7/8): 246. Bibcode:2003MSHT...45..246Z. doi:10.1023/A:1027368032062. S2CID 135389572.
46. Hedrick, James B. . REEhandbook. Pro-Edge.com. Archived from the original on 2012-06-02. Retrieved 2012-05-09.
47. Samstag, Tony (1987). "Star-wars intrigue greets scandium find". New Scientist: 26.
48. Evidence against Anomalous Compositions for Giants in the Galactic Nuclear Star Cluster, B. Thorsbro et al, The Astrophysical Journal, Volume 866, Number 1, 2018-10-10
49. Ahmad, Zaki (2003). "The properties and application of scandium-reinforced aluminum". JOM. 55 (2): 35. Bibcode:2003JOM....55b..35A. doi:10.1007/s11837-003-0224-6. S2CID 8956425.
50. Knipling, Keith E.; Dunand, David C.; Seidman, David N. (2006-03-01). "Criteria for developing castable, creep-resistant aluminum-based alloys – A review". Zeitschrift für Metallkunde. 97 (3): 246–265. doi:10.3139/146.101249. ISSN 0044-3093. S2CID 4681149.
51. Knipling, Keith E.; Karnesky, Richard A.; Lee, Constance P.; Dunand, David C.; Seidman, David N. (2010-09-01). "Precipitation evolution in Al–0.1Sc, Al–0.1Zr and Al–0.1Sc–0.1Zr (at.%) alloys during isochronal aging". Acta Materialia. 58 (15): 5184–5195. Bibcode:2010AcMat..58.5184K. doi:10.1016/j.actamat.2010.05.054. ISSN 1359-6454.
52. Booth-Morrison, Christopher; Dunand, David C.; Seidman, David N. (2011-10-01). "Coarsening resistance at 400°C of precipitation-strengthened Al–Zr–Sc–Er alloys". Acta Materialia. 59 (18): 7029–7042. Bibcode:2011AcMat..59.7029B. doi:10.1016/j.actamat.2011.07.057. ISSN 1359-6454.
53. De Luca, Anthony; Dunand, David C.; Seidman, David N. (2016-10-15). "Mechanical properties and optimization of the aging of a dilute Al-Sc-Er-Zr-Si alloy with a high Zr/Sc ratio". Acta Materialia. 119: 35–42. Bibcode:2016AcMat.119...35D. doi:10.1016/j.actamat.2016.08.018. ISSN 1359-6454.
54. Schwarz, James A.; Contescu, Cristian I.; Putyera, Karol (2004). Dekker encyclopédia of nanoscience and nanotechnology. Vol. 3. CRC Press. p. 2274. ISBN 978-0-8247-5049-7.
55. Youssef, Khaled M.; Zaddach, Alexander J.; Niu, Changning; Irving, Douglas L.; Koch, Carl C. (2015). "A Novel Low-Density, High-Hardness, High-entropy Alloy with Close-packed Single-phase Nanocrystalline Structures". Materials Research Letters. 3 (2): 95–99. doi:10.1080/21663831.2014.985855.
56. Bjerklie, Steve (2006). "A batty business: Anodized metal bats have revolutionized baseball. But are finishers losing the sweet spot?". Metal Finishing. 104 (4): 61. doi:10.1016/S0026-0576(06)80099-1.
57. "Easton Technology Report: Materials / Scandium" (PDF). EastonBike.com. Retrieved 2009-04-03.
58. James, Frank (15 December 2004). Effective handgun defense. Krause Publications. pp. 207–. ISBN 978-0-87349-899-9. Retrieved 2011-06-08.
59. Sweeney, Patrick (13 December 2004). The Gun Digest Book of Smith & Wesson. Gun Digest Books. pp. 34–. ISBN 978-0-87349-792-3. Retrieved 2011-06-08.
60. Nouri, Keyvan (2011-11-09). "History of Laser Dentistry". Lasers in Dermatology and Medicine. pp. 464–465. ISBN 978-0-85729-280-3.
61. Hammond, C. R. in CRC Handbook of Chemistry and Physics 85th ed., Section 4; The Elements.
62. Simpson, Robert S. (2003). Lighting Control: Technology and Applications. Focal Press. p. 108. ISBN 978-0-240-51566-3.
63. "Scandium International Mining" (PDF). Hallgarten & Company.
64. Kobayashi, Shu; Manabe, Kei (2000). "Green Lewis acid catalysis in organic synthesis" (PDF). Pure and Applied Chemistry. 72 (7): 1373–1380. doi:10.1351/pac200072071373. S2CID 16770637.
65. Horovitz, Chaim T.; Birmingham, Scott D. (1999). Biochemistry of Scandium and Yttrium. Springer. ISBN 978-0-306-45657-2.
66. Haley, Thomas J.; Komesu, L.; Mavis, N.; Cawthorne, J.; Upham, H. C. (1962). "Pharmacology and toxicology of scandium chloride". Journal of Pharmaceutical Sciences. 51 (11): 1043–5. doi:10.1002/jps.2600511107. PMID 13952089.
67. Ganrot, P. O. (1986). "Metabolism and Possible Health Effects of Aluminum". Environmental Health Perspectives. 65: 363–441. doi:10.2307/3430204. ISSN 0091-6765. JSTOR 3430204. PMC 1474689. PMID 2940082.

Further reading

• Scerri, Eric R. (2007). The Periodic System: Its Story and Its Significance. Oxford, UK: Oxford University Press. ISBN 9780195305739. OCLC 62766695.

External links

 

Look up scandium in Wiktionary, the free dictionary.

 

Wikimedia Commons has media related to Scandium.

• Scandium at The Periodic Table of Videos (University of Nottingham)
• WebElements.com – Scandium
• "Scandium" . Encyclopædia Britannica (11th ed.). 1911.