Terbium: Difference between revisions
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Most of the world's terbium supply is used in "green" phosphors (which are usually yellow). Terbium [[oxide]] is in [[fluorescent lamp]]s and TV tubes. Terbium "green" [[phosphor]]s (which fluoresce a brilliant lemon-yellow) are combined with divalent [[europium]] blue phosphors and trivalent europium red phosphors to provide "trichromatic" lighting technology, a high-efficiency white light used for standard illumination in indoor lighting. |
Most of the world's terbium supply is used in "green" phosphors (which are usually yellow). Terbium [[oxide]] is in [[fluorescent lamp]]s and TV tubes. Terbium "green" [[phosphor]]s (which fluoresce a brilliant lemon-yellow) are combined with divalent [[europium]] blue phosphors and trivalent europium red phosphors to provide "trichromatic" lighting technology, a high-efficiency white light used for standard illumination in indoor lighting. |
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== James Likes Men == |
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===James is a Huge Flamer=== |
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Terbium is a silvery-white [[Rare earth element|rare earth]] [[metal]] that is [[malleable]], [[ductile]] and soft enough to be cut with a knife. It is relatively stable in air as compared to other lanthanides.<ref>{{cite web| url = http://www.elementsales.com/re_exp/index.htm |title = Rare-Earth Metal Long Term Air Exposure Test| accessdate = 2009-05-05}}</ref> Terbium exists in two crystal [[Allotropy|allotropes]] with a transformation temperature of 1289 °C between them.<ref name=CRC/> |
Terbium is a silvery-white [[Rare earth element|rare earth]] [[metal]] that is [[malleable]], [[ductile]] and soft enough to be cut with a knife. It is relatively stable in air as compared to other lanthanides.<ref>{{cite web| url = http://www.elementsales.com/re_exp/index.htm |title = Rare-Earth Metal Long Term Air Exposure Test| accessdate = 2009-05-05}}</ref> Terbium exists in two crystal [[Allotropy|allotropes]] with a transformation temperature of 1289 °C between them.<ref name=CRC/> |
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| Terbium | ||||||||||||||||||||||||||||
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| Pronunciation | /ˈtɜːrbiəm/ | |||||||||||||||||||||||||||
| Appearance | silvery white | |||||||||||||||||||||||||||
| Standard atomic weight Ar°(Tb) | ||||||||||||||||||||||||||||
| Terbium in the periodic table | ||||||||||||||||||||||||||||
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| Atomic number (Z) | 65 | |||||||||||||||||||||||||||
| Group | f-block groups (no number) | |||||||||||||||||||||||||||
| Period | period 6 | |||||||||||||||||||||||||||
| Block | f-block | |||||||||||||||||||||||||||
| Electron configuration | [Xe] 4f9 6s2 | |||||||||||||||||||||||||||
| Electrons per shell | 2, 8, 18, 27, 8, 2 | |||||||||||||||||||||||||||
| Physical properties | ||||||||||||||||||||||||||||
| Phase at STP | solid | |||||||||||||||||||||||||||
| Melting point | 1629 K (1356 °C, 2473 °F) | |||||||||||||||||||||||||||
| Boiling point | 3396 K (3123 °C, 5653 °F) | |||||||||||||||||||||||||||
| Density (at 20° C) | 8.229 g/cm3 [3] | |||||||||||||||||||||||||||
| when liquid (at m.p.) | 7.65 g/cm3 | |||||||||||||||||||||||||||
| Heat of fusion | 10.15 kJ/mol | |||||||||||||||||||||||||||
| Heat of vaporization | 391 kJ/mol | |||||||||||||||||||||||||||
| Molar heat capacity | 28.91 J/(mol·K) | |||||||||||||||||||||||||||
Vapor pressure
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| Atomic properties | ||||||||||||||||||||||||||||
| Oxidation states | common: +3 0,[4] +1,[5] +2,? +4[6] | |||||||||||||||||||||||||||
| Electronegativity | Pauling scale: 1.2 (?) | |||||||||||||||||||||||||||
| Ionization energies |
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| Atomic radius | empirical: 177 pm | |||||||||||||||||||||||||||
| Covalent radius | 194±5 pm | |||||||||||||||||||||||||||
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| Other properties | ||||||||||||||||||||||||||||
| Natural occurrence | primordial | |||||||||||||||||||||||||||
| Crystal structure | hexagonal close-packed (hcp) (hP2) | |||||||||||||||||||||||||||
| Lattice constants |  c = 569.66 pm (at 20 °C)[3] | |||||||||||||||||||||||||||
| Thermal expansion | at r.t. poly: 10.3 µm/(m⋅K) | |||||||||||||||||||||||||||
| Thermal conductivity | 11.1 W/(m⋅K) | |||||||||||||||||||||||||||
| Electrical resistivity | α, poly: 1.150 µΩ⋅m (at r.t.) | |||||||||||||||||||||||||||
| Magnetic ordering | paramagnetic at 300 K | |||||||||||||||||||||||||||
| Molar magnetic susceptibility | +146000×10−6 cm3/mol (273 K)[7] | |||||||||||||||||||||||||||
| Young's modulus | 55.7 GPa | |||||||||||||||||||||||||||
| Shear modulus | 22.1 GPa | |||||||||||||||||||||||||||
| Bulk modulus | 38.7 GPa | |||||||||||||||||||||||||||
| Speed of sound thin rod | 2620 m/s (at 20 °C) | |||||||||||||||||||||||||||
| Poisson ratio | 0.261 | |||||||||||||||||||||||||||
| Vickers hardness | 450–865 MPa | |||||||||||||||||||||||||||
| Brinell hardness | 675–1200 MPa | |||||||||||||||||||||||||||
| CAS Number | 7440-27-9 | |||||||||||||||||||||||||||
| History | ||||||||||||||||||||||||||||
| Naming | after Ytterby (Sweden), where it was mined | |||||||||||||||||||||||||||
| Discovery and first isolation | Carl Gustaf Mosander (1843) | |||||||||||||||||||||||||||
| Isotopes of terbium | ||||||||||||||||||||||||||||
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Terbium (/[invalid input: 'icon']ˈtɜːrbiəm/ TUR-bee-əm) is a chemical element with the symbol Tb and atomic number 65. It is a silvery-white rare earth metal that is malleable, ductile and soft enough to be cut with a knife. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite.
Terbium is used to dope calcium fluoride, calcium tungstate and strontium molybdate, materials that are used in solid-state devices, and as a crystal stabilizer of fuel cells which operate at elevated temperatures. As a component of Terfenol-D (an alloy that expands and contracts when exposed to magnetic fields more than any other alloy), terbium is of use in actuators, in naval sonar systems and in sensors.
Most of the world's terbium supply is used in "green" phosphors (which are usually yellow). Terbium oxide is in fluorescent lamps and TV tubes. Terbium "green" phosphors (which fluoresce a brilliant lemon-yellow) are combined with divalent europium blue phosphors and trivalent europium red phosphors to provide "trichromatic" lighting technology, a high-efficiency white light used for standard illumination in indoor lighting.
James Likes Men
James is a Huge Flamer
Terbium is a silvery-white rare earth metal that is malleable, ductile and soft enough to be cut with a knife. It is relatively stable in air as compared to other lanthanides.[9] Terbium exists in two crystal allotropes with a transformation temperature of 1289 °C between them.[10]
The terbium(III) cation is brilliantly fluorescent, in a bright lemon-yellow color that is the result of a strong green emission line in combination with other lines in the orange and red. The yttrofluorite variety of the mineral fluorite owes its creamy-yellow fluorescence in part to terbium. Terbium easily oxidizes, and is therefore used in its elemental form specifically for research. Single Tb atoms have been isolated by implanting them into fullerene molecules.[11]
Terbium has a simple ferromagnetic ordering at temperatures below 219 K. Above 219 K, it turns into a helical antiferromagnetic state in which all of the atomic moments in a particular basal plane layer are parallel, and oriented at a fixed angle to the moments of adjacent layers. This unusual antiferromagnetism transforms into a disordered paramagnetic state at 230 K.[12]
Chemical properties
The most common valence state of terbium is +3, as in Tb
2O
3. The +4 state is known in TbO2 and TbF4.[13][14]
Terbium burns readily to form a mixed terbium(III,IV) oxide:[15]
- 8 Tb + 7 O2 → 2 Tb4O7
In solution, terbium forms only trivalent ions. Terbium is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form terbium hydroxide:[15]
- 2 Tb + 6 H2O → 2 Tb(OH)3 + 3 H2↑
Terbium metal reacts with all the halogens, forming white trihalides:[15]
Terbium dissolves readily in dilute sulfuric acid to form solutions containing the pale pink terbium(III) ions, which exist as a [Tb(OH2)9]3+ complexes:[15]
- 2 Tb (s) + 3 H2SO4 → 2 Tb3+ + 3 SO2−
4 + 3 H2↑
Compounds
Terbium combines with nitrogen, carbon, sulfur, phosphorus, boron, selenium, silicon and arsenic at elevated temperatures, forming various binary compounds such as TbH2, TbH3, TbB2, Tb2S3, TbSe, TbTe and TbN.[14] In those compounds, Tb mostly exhibit oxidation states +3 and sometimes +2. Terbium(II) halogenides are obtained by annealing Tb(III) halogenides in presence of metallic Tb in tantalum containers. Terbium also forms sesquichloride Tb2Cl3, which can be further reduced to TbCl by annealing at 800 °C. This terbium(I) chloride forms platelets with layered graphite-like structure.[16]
Other compounds include
Terbium(IV) fluoride is a strong fluorinating agent, emitting relatively pure atomic fluorine when heated[17] rather than the mixture of fluoride vapors emitted from CoF3 or CeF4.
Isotopes
Naturally occurring terbium is composed of its only stable isotope, terbium-159; the element is thus called mononuclidic and monoisotopic. 36 radioisotopes have been characterized, with the heaviest being terbium-171 (with atomic mass of 170.95330(86) u) and lightest being terbium-135 (exact mass unknown).[18] The most stable synthetic radioisotope of terbium are terbium-158, with a half-life of 180 years, and terbium-157, with a half-life of 71 years. All of the remaining radioactive isotopes have half-lives that are well less than quarter a year, and the majority of these have half-lives that are less than half a minute.[18] The primary decay mode before the most abundant stable isotope, 159Tb, is electron capture, which results in production of gadolinium isotopes, and the primary mode after is beta minus decay, resulting in dysprosium isotopes.[18]
The element also has 27 nuclear isomers, with masses of 141—154, 156, and 158 (not every mass number corresponds to only one isomer). The most stable of them are terbium-156m, with half-life of 24.4 hours and terbium-156m2, with half-life of 22.7 hours; this is longer than half-lives of most ground states of radioactive terbium isotopes, except only those with mass numbers 155—161.[18]
History
Terbium was discovered in 1843 by Swedish chemist Carl Gustaf Mosander, who detected it as an impurity in Yttrium oxide, Y2O3, and named after the village Ytterby in Sweden. It was not isolated in pure form until the recent advent of ion exchange techniques.[19]
When Mosander first partitioned "yttria" into three fractions, "terbia" was the fraction that contained the pink color (due to what is now known as erbium), and "erbia" was the fraction that was essentially colorless in solution, but gave a brown-tinged oxide. Later workers had difficulty in observing the latter, but the pink fraction was impossible to miss. Arguments went back and forth as to whether "erbia" even existed. In the confusion, the original names got reversed, and the exchange of names stuck. It is now thought that those workers who used the double sodium or potassium sulfates to remove "ceria" from "yttria" inadvertently lost the terbium content of the system into the ceria-containing precipitate. In any case, what is now known as terbium was only about 1% of the original yttria, but that was sufficient to impart a yellowish color to the oxide. Thus, terbium was a minor component in the original terbium fraction, dominated by its immediate neighbors, gadolinium and dysprosium. Thereafter, whenever other rare earths were teased apart from this mixture, whichever fraction gave the brown oxide retained the terbium name, until at last it was pure. The 19th century investigators did not have the benefit of fluorescence technology, wherewith to observe the brilliant fluorescence that would have made this element much easier to track in mixtures.[19]
Occurrence
Terbium is never found in nature by itself, but is contained along with other rare earth elements in many minerals, including monazite ((Ce,La,Th,Nd,Y)PO4 with up to 0.03% terbium), xenotime (YPO4) and euxenite ((Y,Ca,Er,La,Ce,U,Th)(Nb,Ta,Ti)2O6 with 1% or more terbium). The crust abundance of terbium is estimated as 1.2 mg/kg.[14]
Currently, the richest commercial sources of terbium are the ion-adsorption clays of southern China; the concentrates with about two-thirds yttrium oxide by weight have about 1% terbia. Small amounts of terbium occur in bastnäsite and monazite; when these are processed by solvent extraction to recover the valuable heavy lanthanides as samarium-europium-gadolinium concentrate, terbium is recovered therein. Due to the large volumes of bastnäsite processed relative to the ion-adsorption clays, a significant proportion of the world's terbium supply comes from bastnäsite.[10]
Production
Crushed terbium-containing minerals are treated with hot concentrated sulfuric acid to produce water-soluble sulfates of rare earths. The acidic filtrates are partially neutralized with caustic soda to pH 3-4. Thorium precipitates out of solution as hydroxide and is removed. After that the solution is treated with ammonium oxalate to convert rare earths into their insoluble oxalates. The oxalates are converted to oxides by annealing. The oxides are dissolved in nitric acid that excludes one of the main components, cerium, whose oxide is insoluble in HNO3. Terbium is separated as a double salt with ammonium nitrate by crystallization.[14]
The most efficient separation routine for terbium salt from the rare-earth salt solution is ion exchange. In this process, rare-earth ions are sorbed onto suitable ion-exchange resin by exchange with hydrogen, ammonium or cupric ions present in the resin. The rare earth ions are then selectively washed out by suitable complexing agent. As with other rare earths, terbium metal is produced by reducing the anhydrous chloride or fluoride with calcium metal. Calcium and tantalum impurities can be removed by vacuum remelting, distillation, amalgam formation or zone melting.[14]
Applications
Terbium is used as a Dopant in calcium fluoride, calcium tungstate and strontium molybdate, materials that are used in solid-state devices, and as a crystal stabilizer of fuel cells which operate at elevated temperatures, together with ZrO2.[10]
Terbium is also used in alloys and in the production of electronic devices. As a component of Terfenol-D, terbium is of use in actuators, in naval sonar systems, sensors, in the SoundBug device (its first commercial application), and other magnetomechanical devices. Terfenol-D is an alloy that expands or contracts in the presence of a magnetic field. It has the highest magnetostriction of any alloy.[20]
Terbium oxide is used in green phosphors in fluorescent lamps and color TV tubes. Sodium terbium borate is used in solid state devices. The brilliant fluorescence allows terbium to be used as a probe in biochemistry, where it somewhat resembles calcium in its behavior. Terbium "green" phosphors (which fluoresce a brilliant lemon-yellow) are combined with divalent europium blue phosphors and trivalent europium red phosphors to provide the "trichromatic" lighting technology which is by far the largest consumer of the world's terbium supply. Trichromatic lighting provides much higher light output for a given amount of electrical energy than does incandescent lighting.[10]
Precautions
As with the other lanthanides, terbium compounds are of low to moderate toxicity, although their toxicity has not been investigated in detail. Terbium has no known biological role.[10]
References
- ^ "Standard Atomic Weights: Terbium". CIAAW. 2021.
- ^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
- ^ a b Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.
- ^ Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24. doi:10.1039/CS9932200017. and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry. 688 (1–2): 49–55. doi:10.1016/j.jorganchem.2003.08.028.
- ^ La(I), Pr(I), Tb(I), Tm(I), and Yb(I) have been observed in MB8− clusters; see Li, Wan-Lu; Chen, Teng-Teng; Chen, Wei-Jia; Li, Jun; Wang, Lai-Sheng (2021). "Monovalent lanthanide(I) in borozene complexes". Nature Communications. 12 (1): 6467. doi:10.1038/s41467-021-26785-9. PMC 8578558. PMID 34753931.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 28. ISBN 978-0-08-037941-8.
- ^ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
- ^ 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.
- ^ "Rare-Earth Metal Long Term Air Exposure Test". Retrieved 2009-05-05.
- ^ a b c d e C. R. Hammond, "The Elements", in Handbook of Chemistry and Physics 81st edition, CRC press.
- ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/j.physe.2003.11.197, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1016/j.physe.2003.11.197instead. - ^ M. Jackson (2000). "Magnetism of Rare Earth" (PDF). The IRM quarterly. 10 (3): 1.
- ^ D.M. Gruen, W.C. Koehler, and J.J. Katz (April 1951). "Higher Oxides of the Lanthanide Elements: Terbium Dioxide" (PDF). Journal of the American Chemical Society. 73 (4): 1475–9. doi:10.1021/ja01148a020.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ a b c d e Patnaik, Pradyot (2003). Handbook of Inorganic Chemical Compounds. McGraw-Hill. pp. 920–921. ISBN 0-07-049439-8. Retrieved 2009-06-06.
- ^ a b c d "Chemical reactions of Terbium". Webelements. Retrieved 2009-06-06.
- ^ Cotton (2007). Advanced inorganic chemistry, 6th ed. Wiley-India. p. 1128. ISBN 81-265-1338-1.
- ^ J.V.Rau (2001). "Transition and rare earth metal fluorides as thermal sources of atomic and molecular fluorine".
{{cite journal}}: Cite journal requires|journal=(help); Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ a b c d G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ a b C. K. Gupta, Nagaiyar Krishnamurthy (2004). Extractive metallurgy of rare earths. CRC Press. p. 5. ISBN 0-415-33340-7.
- ^ Rodriguez, C; Rodriguez, M; Orue, I; Vilas, J; Barandiaran, J; Gubieda, M; Leon, L (2009). "New elastomer–Terfenol-D magnetostrictive composites". Sensors and Actuators A: Physical. 149 (2): 251. doi:10.1016/j.sna.2008.11.026.
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