DYSPROSIUM

introduction

Numéro atomique: 66
Groupe: Aucun
Poids atomique: 162.5
Période: 6
Numero CAS: 7429-91-6

Classification

chalcogènes
Halogène
Gaz rare
lanthanides
actinides
Rare Earth Element
Groupe Platine Métal
Transuranium
Pas d'isotopes stables
Solide
Liquide
Gaz
Solide (prédit)

La description • Usages / Fonction

Dysprosium was discovered in 1886 by Lecoq de Boisbaudran, but not isolated. Neither the oxide nor the metal was available in relatively pure formuntil the development of ion-exchange separation and metallographic reduction techniques by Spedding and associates about 1950. Dysprosium occursalong with other so-called rare-earth or lanthanide elements in a variety of minerals such as xenotime, fergusonite, gadolinite, euxenite, polycrase, andblomstrandine. The most important sources, however, are from monazite and bastnasite. Dysprosium can be prepared by reduction of the trifluoridewith calcium. The element has a metallic, bright silver luster. It is relatively stable in air at room temperature, and is readily attacked and dissolved,with the evolution of hydrogen, by dilute and concentrated mineral acids. The metal is soft enough to be cut with a knife and can be machined withoutsparking if overheating is avoided. Small amounts of impurities can greatly affect its physical properties. While dysprosium has not yet found manyapplications, its thermal neutron absorption cross-section and high melting point suggest metallurgical uses in nuclear control applications and foralloying with special stainless steels. A dysprosium oxide-nickel cermet has found use in cooling nuclear reactor rods. This cermet absorbs neutronsreadily without swelling or contracting under prolonged neutron bombardment. In combination with vanadium and other rare earths, dysprosium hasbeen used in making laser materials. Dysprosium-cadmium chalcogenides, as sources of infrared radiation, have been used for studying chemicalreactions. The cost of dysprosium metal has dropped in recent years since the development of ion-exchange and solvent extraction techniques, andthe discovery of large ore bodies. Thirty two isotopes and isomers are now known. The metal costs about $4/g (99.9% purity). 1

• "Some power tools rely on...dysprosium magnets to shrink their motors." 2

Propriétés physiques

Point de fusion:3*  1412 °C = 1685.15 K = 2573.6 °F
Point d'ébullition:3* 2567 °C = 2840.15 K = 4652.6 °F
sublimation point:3 
Triple point:3 
Point critique:3 
Densité:4  8.55 g/cm3

* - at 1 atm

Configuration de l'électron

Configuration de l'électron:  *[Xe] 6s2 4f10
Bloque: f
Plus haut niveau d'énergie occupés: 6
Électrons de valence: 2

Nombres quantiques:

n = 4
ℓ = 3
m = -1
ms = -½

Bonding

Électronégativité (échelle de Pauling):5 1.22
Electropositivity (échelle de Pauling): 2.78

ionisation potentiel   eV 6  kJ/mol  
1 5.9389    573.0
ionisation potentiel   eV 6  kJ/mol  
2 11.67    1126.0
ionisation potentiel   eV 6  kJ/mol  
3 22.8    2199.9
4 41.47    4001.2

Thermochimie

Chaleur spécifique: 0.170 J/g°C 7 = 27.625 J/mol°C = 0.041 cal/g°C = 6.603 cal/mol°C
Conductivité thermique: 10.7 (W/m)/K, 27°C 8
Température de fusion: 11.06 kJ/mol 9 = 68.1 J/g
Chaleur de vaporisation: 230.1 kJ/mol 10 = 1416.0 J/g
État de la matière Enthalpie de formation (ΔHf°)11 Entropy (S°)11 Gibbs Free Energy (ΔGf°)11
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(s) 0 0 18.0 75.312 0 0
(g) 59.4 248.5296 46.97 196.52248 60.8 254.3872

isotopes

Nuclide Masse 12 Demi vie 12 Spin nucléaire 12 Énergie de liaison
138Dy 137.96249(64)# 200# ms 0+ 1,099.46 MeV
139Dy 138.95954(54)# 600(200) ms 7/2+# 1,116.85 MeV
140Dy 139.95401(54)# 700# ms 0+ 1,124.92 MeV
141Dy 140.95135(32)# 0.9(2) s (9/2-) 1,132.99 MeV
142Dy 141.94637(39)# 2.3(3) s 0+ 1,150.38 MeV
143Dy 142.94383(21)# 5.6(10) s (1/2+) 1,158.45 MeV
144Dy 143.93925(3) 9.1(4) s 0+ 1,175.84 MeV
145Dy 144.93743(5) 9.5(10) s (1/2+) 1,183.91 MeV
146Dy 145.932845(29) 33.2(7) s 0+ 1,191.98 MeV
147Dy 146.931092(21) 40(10) s 1/2+ 1,200.05 MeV
148Dy 147.927150(11) 3.3(2) min 0+ 1,217.44 MeV
149Dy 148.927305(9) 4.20(14) min 7/2(-) 1,225.51 MeV
150Dy 149.925585(5) 7.17(5) min 0+ 1,233.58 MeV
151Dy 150.926185(4) 17.9(3) min 7/2(-) 1,241.65 MeV
152Dy 151.924718(6) 2.38(2) h 0+ 1,249.72 MeV
153Dy 152.925765(5) 6.4(1) h 7/2(-) 1,257.79 MeV
154Dy 153.924424(8) 3.0(15)E+6 a 0+ 1,265.87 MeV
155Dy 154.925754(13) 9.9(2) h 3/2- 1,273.94 MeV
156Dy 155.924283(7) STABLE 0+ 1,282.01 MeV
157Dy 156.925466(7) 8.14(4) h 3/2- 1,290.08 MeV
158Dy 157.924409(4) STABLE 0+ 1,298.15 MeV
159Dy 158.9257392(29) 144.4(2) d 3/2- 1,306.22 MeV
160Dy 159.9251975(27) STABLE 0+ 1,314.29 MeV
161Dy 160.9269334(27) STABLE 5/2+ 1,322.36 MeV
162Dy 161.9267984(27) STABLE 0+ 1,330.44 MeV
163Dy 162.9287312(27) STABLE 5/2- 1,338.51 MeV
164Dy 163.9291748(27) STABLE 0+ 1,346.58 MeV
165Dy 164.9317033(27) 2.334(1) h 7/2+ 1,345.34 MeV
166Dy 165.9328067(28) 81.6(1) h 0+ 1,353.41 MeV
167Dy 166.93566(6) 6.20(8) min (1/2-) 1,361.48 MeV
168Dy 167.93713(15) 8.7(3) min 0+ 1,369.55 MeV
169Dy 168.94031(32) 39(8) s (5/2-) 1,368.31 MeV
170Dy 169.94239(21)# 30# s 0+ 1,376.38 MeV
171Dy 170.94620(32)# 6# s 7/2-# 1,384.45 MeV
172Dy 171.94876(43)# 3# s 0+ 1,392.52 MeV
173Dy 172.95300(54)# 2# s 9/2+# 1,391.28 MeV
Les valeurs marquées # ne sont pas purement dérivées des données expérimentales, mais au moins en partie des tendances systématiques. Spins avec de faibles arguments d'affectation sont entre parenthèses. 12

Réactions

Abondance

Terre - composés Source: phosphates 13
Terre - Seawater: 0.00000091 mg/L 14
Terre -  Croûte:  5.2 mg/kg = 0.00052% 14
Terre -  Total:  364 ppb 15
Planète Mercure) -  Total:  280 ppb 15
Vénus -  Total:  382 ppb 15
chondrites - Total: 0.33 (relative to 106 atoms of Si) 16

composés

Information de sécurité


Fiche signalétique - ACI Alloys, Inc.

Pour plus d'informations

Liens externes:

Les magazines:
(1) Folger, Tim. The Secret Ingredients of Everything. National Geographic, June 2011, pp 136-145.

Sources

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:10.
(2) - Folger, Tim. The Secret Ingredients of Everything. National Geographic, June 2011, p 140.
(3) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(4) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(5) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(6) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(7) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(11) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(12) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(13) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(14) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(15) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(16) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.