サマリウム

導入

原子番号: 62
グループ: なし
原子量: 150.36
期間: 6
CAS番号: 7440-19-9

分類

カルコゲン
ハロゲン
希ガス
ランタノイド元素
アクチノイド元素
希土類元素
プラチナグループメタル
超ウラン
いいえ安定同位体ません
固体
液体
ガス
固体 (予測)

説明 • 用途/機能

Discovered spectroscopically by its sharp absorption lines in 1879 by Lecoq de Boisbaudran in the mineral samarskite, named in honor of a Russianmine official, Col. Samarski. Samarium is found along with other members of the rare-earth elements in many minerals, including monazite andbastnasite, which are commercial sources. It occurs in monazite to the extent of 2.8%. While misch metal containing about 1% of samarium metal,has long been used, samarium has not been isolated in relatively pure form until recent years. Ion-exchange and solvent extraction techniques haverecently simplified separation of the rare earths from one another; more recently, electrochemical deposition, using an electrolytic solution of lithiumcitrate and a mercury electrode, is said to be a simple, fast, and highly specific way to separate the rare earths. Samarium metal can be produced byreducing the oxide with barium or lanthanum. Samarium has a bright silver luster and is reasonably stable in air. Three crystal modifications of themetal exist, with transformations at 734 and 922°C. The metal ignites in air at about 150°C. Thirty two isotopes and isomers of samarium are nowrecognized. Natural samarium is a mixture of seven isotopes, three of which are unstable but have long half-lives. Samarium, along with other rareearths, is used for carbon-arc lighting for the motion picture industry. The sulfide has excellent high-temperature stability and good thermoelectricefficiencies up to 1100°C. SmCo5 has been used in making a new permanent magnet material with the highest resistance to demagnetization of anyknown material. It is said to have an intrinsic coercive force as high as 2200 kA/m. Samarium oxide has been used in optical glass to absorb the infrared.Samarium is used to dope calcium fluoride crystals for use in optical masers or lasers. Compounds of the metal act as sensitizers for phosphors excitedin the infrared; the oxide exhibits catalytic properties in the dehydration and dehydrogenation of ethyl alcohol. It is used in infrared absorbing glassand as a neutron absorber in nuclear reactors. The metal is priced at about $2/g (99.9%). Little is known of the toxicity of samarium; therefore, it shouldbe handled carefully. 1

• "Samarium magnets, which can withstand intense heat, help control Predator drones and Tomahawk cruise missiles." 2

物理的特性

融点:3*  1074 °C = 1347.15 K = 1965.2 °F
沸点:3* 1794 °C = 2067.15 K = 3261.2 °F
昇華点:3 
三重点:3 
臨界点:3 
密度:4  7.52 g/cm3

* - at 1 atm

電子構成

電子構成:  *[Xe] 6s2 4f6
ブロック: f
最高占有エネルギーレベル: 6
ヴァランス電子: 2

量子数:

n = 4
ℓ = 3
m = 2
ms = +½

ボンディング

電気陰性度 (ポーリングスケール):5 1.17
Electropositivity (ポーリングスケール): 2.83
仕事関数:6 2.95 eV = 4.7259E-19 J

イオン化ポテンシャル   eV 7  kJ/mol  
1 5.6436    544.5
イオン化ポテンシャル   eV 7  kJ/mol  
2 11.07    1068.1
イオン化ポテンシャル   eV 7  kJ/mol  
3 23.4    2257.8
4 41.4    3994.5

熱化学

比熱: 0.197 J/g°C 8 = 29.621 J/mol°C = 0.047 cal/g°C = 7.080 cal/mol°C
熱伝導率: 13.3 (W/m)/K, 27°C 9
融解熱: 8.63 kJ/mol 10 = 57.4 J/g
気化熱: 166.4 kJ/mol 11 = 1106.7 J/g
物質の状態 生成エンタルピー (ΔHf°)12 エントロピ (S°)12 ギブズ自由エネルギー (ΔGf°)12
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(s) 0 0 16.63 69.57992 0 0
(g) 49.4 206.6896 43.72 182.92448 41.3 172.7992

同位体

核種 質量 13 人生の半分 13 核スピン 13 結合エネルギー
128Sm 127.95808(54)# 0.5# s 0+ 1,031.20 MeV
129Sm 128.95464(54)# 550(100) ms 5/2+# 1,039.27 MeV
130Sm 129.94892(43)# 1# s 0+ 1,056.65 MeV
131Sm 130.94611(32)# 1.2(2) s 5/2+# 1,064.72 MeV
132Sm 131.94069(32)# 4.0(3) s 0+ 1,072.80 MeV
133Sm 132.93867(21)# 2.90(17) s (5/2+) 1,090.18 MeV
134Sm 133.93397(21)# 10(1) s 0+ 1,098.25 MeV
135Sm 134.93252(17) 10.3(5) s (7/2+) 1,106.33 MeV
136Sm 135.928276(13) 47(2) s 0+ 1,123.71 MeV
137Sm 136.92697(5) 45(1) s (9/2-) 1,131.78 MeV
138Sm 137.923244(13) 3.1(2) min 0+ 1,139.85 MeV
139Sm 138.922297(12) 2.57(10) min 1/2+ 1,147.93 MeV
140Sm 139.918995(13) 14.82(12) min 0+ 1,165.31 MeV
141Sm 140.918476(9) 10.2(2) min 1/2+ 1,173.38 MeV
142Sm 141.915198(6) 72.49(5) min 0+ 1,181.45 MeV
143Sm 142.914628(4) 8.75(8) min 3/2+ 1,189.53 MeV
144Sm 143.911999(3) STABLE 0+ 1,197.60 MeV
145Sm 144.913410(3) 340(3) d 7/2- 1,205.67 MeV
146Sm 145.913041(4) 1.03(5)E+8 a 0+ 1,213.74 MeV
147Sm 146.9148979(26) 1.06(2)E+11 a 7/2- 1,221.81 MeV
148Sm 147.9148227(26) 7(3)E+15 a 0+ 1,229.88 MeV
149Sm 148.9171847(26) STABLE 7/2- 1,237.95 MeV
150Sm 149.9172755(26) STABLE 0+ 1,246.02 MeV
151Sm 150.9199324(26) 90(8) a 5/2- 1,254.10 MeV
152Sm 151.9197324(27) STABLE 0+ 1,262.17 MeV
153Sm 152.9220974(27) 46.284(4) h 3/2+ 1,260.92 MeV
154Sm 153.9222093(27) STABLE 0+ 1,269.00 MeV
155Sm 154.9246402(28) 22.3(2) min 3/2- 1,277.07 MeV
156Sm 155.925528(10) 9.4(2) h 0+ 1,285.14 MeV
157Sm 156.92836(5) 8.03(7) min (3/2-) 1,293.21 MeV
158Sm 157.92999(8) 5.30(3) min 0+ 1,301.28 MeV
159Sm 158.93321(11) 11.37(15) s 5/2- 1,300.04 MeV
160Sm 159.93514(21)# 9.6(3) s 0+ 1,308.11 MeV
161Sm 160.93883(32)# 4.8(8) s 7/2+# 1,316.18 MeV
162Sm 161.94122(54)# 2.4(5) s 0+ 1,314.94 MeV
163Sm 162.94536(75)# 1# s 1/2-# 1,323.01 MeV
164Sm 163.94828(86)# 500# ms 0+ 1,331.08 MeV
165Sm 164.95298(97)# 200# ms 5/2-# 1,329.83 MeV
値は、#は、純粋に実験データから派生しますが、少なくとも部分的に体系的な傾向からしていないとマーク。弱い代入引数は括弧で囲まれていてスピン。 13

豊富

地球 - ソース化合物: phosphates 14
地球 - 海水: 0.00000045 mg/L 15
地球 -  地殻:  7.05 mg/kg = 0.000705% 15
地球 -  合計:  208 ppb 16
マーキュリー(惑星) -  合計:  160 ppb 16
金星 -  合計:  218 ppb 16
コンドライト - 合計: 0.23 (relative to 106 atoms of Si) 17

化合物

安全情報


安全データシート - ACI Alloys, Inc.

詳細については

外部リンク:

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

ソース

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:27.
(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) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(7) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(12) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(13) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(14) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(15) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(16) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(17) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.