EUROPIUM

Introduction

Atomic Number: 63
Group: None
Atomic Weight: 151.964
Period: 6
CAS Number: 7440-53-3

Classification

Chalcogen
Halogen
Noble Gas
Lanthanoid
Actinoid
Rare Earth Element
Platinum Group Metal
Transuranium
No Stable Isotopes
Solid
Liquid
Gas
Solid (Predicted)

Description • Uses/Function

In 1890 Boisbaudranobtained basic fractions from samarium-gadolinium concentrates which had spark spectral lines not accounted for by samarium or gadolinium. Theselines subsequently have been shown to belong to europium. The discovery of europium is generally credited to Demarcay, who separated the rare earthin reasonably pure form in 1901. The pure metal was not isolated until recent years. Europium is now prepared by mixing Eu2O3 with a 10%-excessof lanthanum metal and heating the mixture in a tantalum crucible under high vacuum. The element is collected as a silvery-white metallic depositon the walls of the crucible. As with other rare-earth metals, except for lanthanum, europium ignites in air at about 150 to 180°C. Europium is aboutas hard as lead and is quite ductile. It is the most reactive of the rare-earth metals, quickly oxidizing in air. It resembles calcium in its reaction withwater. Bastnasite and monazite are the principal ores containing europium. Europium has been identified spectroscopically in the sun and certain stars.Europium isotopes are good neutron absorbers and are being studied for use in nuclear control applications. Europium oxide is now widely used asa phosphor activator and europium-activated yttrium vanadate is in commercial use as the red phosphor in color TV tubes. Europium-doped plastichas been used as a laser material. With the development of ion-exchange techniques and special processes, the cost of the metal has been greatly reducedin recent years. Natural europium contains two stable isotopes. Thirty five other radioactive isotopes and isomers are known. Europium is one of therarest and most costly of the rare-earth metals. It is priced at about $50/g (99.9% pure). 1

Physical Properties

Melting Point:2*  822 °C = 1095.15 K = 1511.6 °F
Boiling Point:2* 1529 °C = 1802.15 K = 2784.2 °F
Sublimation Point:2 
Triple Point:2 
Critical Point:2 
Density:3  5.24 g/cm3

* - at 1 atm

Electron Configuration

Electron Configuration:  *[Xe] 6s2 4f7
Block: f
Highest Occupied Energy Level: 6
Valence Electrons: 2

Quantum Numbers:

n = 4
ℓ = 3
m = 3
ms = +½

Bonding

Work Function:4 2.50 eV = 4.005E-19 J

Ionization Potential   eV 5  kJ/mol  
1 5.6704    547.1
Ionization Potential   eV 5  kJ/mol  
2 11.241    1084.6
Ionization Potential   eV 5  kJ/mol  
3 24.92    2404.4
4 42.7    4119.9

Thermochemistry

Specific Heat: 0.182 J/g°C 6 = 27.657 J/mol°C = 0.043 cal/g°C = 6.610 cal/mol°C
Thermal Conductivity: 13.9 (W/m)/K, 27°C 7
Heat of Fusion: 9.21 kJ/mol 8 = 60.6 J/g
Heat of Vaporization: 143.5 kJ/mol 9 = 944.3 J/g
State of Matter Enthalpy of Formation (ΔHf°)10 Entropy (S°)10 Gibbs Free Energy (ΔGf°)10
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(s) 0 0 18.59 77.78056 0 0
(g) 41.9 175.3096 45.10 188.6984 34.0 142.256

Isotopes

Nuclide Mass 11 Half-Life 11 Nuclear Spin 11 Binding Energy
130Eu 129.96357(54)# 1.1(5) ms [0.9(+5-3) ms] 2+# 1,037.24 MeV
131Eu 130.95775(43)# 17.8(19) ms 3/2+ 1,054.63 MeV
132Eu 131.95437(43)# 100# ms 1,062.70 MeV
133Eu 132.94924(32)# 200# ms 11/2-# 1,080.09 MeV
134Eu 133.94651(21)# 0.5(2) s 1,088.16 MeV
135Eu 134.94182(32)# 1.5(2) s 11/2-# 1,096.23 MeV
136Eu 135.93960(21)# 3.3(3) s (7+) 1,113.61 MeV
137Eu 136.93557(21)# 8.4(5) s 11/2-# 1,121.69 MeV
138Eu 137.93371(3) 12.1(6) s (6-) 1,129.76 MeV
139Eu 138.929792(14) 17.9(6) s (11/2)- 1,147.14 MeV
140Eu 139.92809(6) 1.51(2) s 1+ 1,155.21 MeV
141Eu 140.924931(14) 40.7(7) s 5/2+ 1,163.29 MeV
142Eu 141.92343(3) 2.36(10) s 1+ 1,171.36 MeV
143Eu 142.920298(12) 2.59(2) min 5/2+ 1,179.43 MeV
144Eu 143.918817(12) 10.2(1) s 1+ 1,196.81 MeV
145Eu 144.916265(4) 5.93(4) d 5/2+ 1,204.89 MeV
146Eu 145.917206(7) 4.61(3) d 4- 1,212.96 MeV
147Eu 146.916746(3) 24.1(6) d 5/2+ 1,221.03 MeV
148Eu 147.918086(11) 54.5(5) d 5- 1,229.10 MeV
149Eu 148.917931(5) 93.1(4) d 5/2+ 1,237.17 MeV
150Eu 149.919702(7) 36.9(9) a 5(-) 1,245.24 MeV
151Eu 150.9198502(26) 5E18 a 5/2+ 1,253.31 MeV
152Eu 151.9217445(26) 13.537(6) a 3- 1,252.07 MeV
153Eu 152.9212303(26) STABLE 5/2+ 1,260.14 MeV
154Eu 153.9229792(26) 8.593(4) a 3- 1,268.21 MeV
155Eu 154.9228933(27) 4.7611(13) a 5/2+ 1,276.28 MeV
156Eu 155.924752(6) 15.19(8) d 0+ 1,284.36 MeV
157Eu 156.925424(6) 15.18(3) h 5/2+ 1,292.43 MeV
158Eu 157.92785(8) 45.9(2) min (1-) 1,300.50 MeV
159Eu 158.929089(8) 18.1(1) min 5/2+ 1,308.57 MeV
160Eu 159.93197(22)# 38(4) s 1(-) 1,307.33 MeV
161Eu 160.93368(32)# 26(3) s 5/2+# 1,315.40 MeV
162Eu 161.93704(32)# 10.6(10) s 1,323.47 MeV
163Eu 162.93921(54)# 6# s 5/2+# 1,331.54 MeV
164Eu 163.94299(64)# 2# s 1,330.30 MeV
165Eu 164.94572(75)# 1# s 5/2+# 1,338.37 MeV
166Eu 165.94997(86)# 400# ms 1,346.44 MeV
167Eu 166.95321(86)# 200# ms 5/2+# 1,345.20 MeV
Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses. 11

Reactions

Abundance

Earth - Source Compounds: phosphates 12
Earth - Seawater: 0.00000013 mg/L 13
Earth -  Crust:  2 mg/kg = 0.0002% 13
Earth -  Total:  79 ppb 14
Mercury -  Total:  61 ppb 14
Venus -  Total:  83 ppb 14
Chondrites - Total: 0.082 (relative to 106 atoms of Si) 15

Compounds

Safety Information


Material Safety Data Sheet - ACI Alloys, Inc.

For More Information

External Links:

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 4:11-4:12.
(2) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(3) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(4) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(5) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(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.