Thallium (Tl)
post-transition-metalSolid
標準原子量
204.38 u [204.382, 204.385]電子配置
[Xe] 6s2 4f14 5d10 6p1融点
303.85 °C沸点
1472.85 °C密度
1.18e+4 kg/m³酸化数
−5, −2, −1, +1, +2, +3電気陰性度（Pauling）
1.62第1イオン化エネルギー
6.108287 eV発見年
1861原子半径
190 pm詳細
Thallium is a soft post-transition metal in group 13. It is chemically notable for the stability of the +1 oxidation state, which reflects the inert-pair effect and makes many thallium(I) salts resemble alkali-metal salts in size and solubility behavior. The element is rare in ores and is usually recovered as a by-product of processing sulfide minerals. Its severe toxicity has greatly reduced former consumer and agricultural uses.
When freshly exposed to air, thallium exhibits a metallic luster, but soon develops a bluish-gray tinge, resembling lead in appearance. A heavy oxide builds up on thallium if left in air, and in the presence of water the hydride is formed. The metal is very soft and malleable. It can be cut with a knife. Twenty five isotopic forms of thallium, with atomic masses ranging from 184 to 210 are recognized. Natural thallium is a mixture of two isotopes. A mercury-thallium alloy, which forms a eutectic at 8.5% thallium, is reported to freeze at -60C, some 20 degrees below the freezing point of mercury.
The name derives from the Greek thallos for "green shoot" or "twig" because of the bright green line in its spectrum. Thallium was discovered by the English physicist and chemist William Crookes in 1861. Metallic thallium was first isolated by the French chemist Claude-Auguste Lamy in 1862.
Thallium was discovered spectroscopically by Sir William Crookes, an English chemist, in 1861. Crooks had obtained the sludge left over from the production of sulfuric acid (H2SO4) from a friend. After removing all of the selenium from the sludge, he inspected it with a device known as a spectroscope to look for signs of tellurium. Rather than seeing the yellow spectral lines produced by tellurium, he observed a bright green line that no one had ever seen before. He named the new element that was producing the green line thallium, after the greek word for 'green twig', thallos. He isolated samples of thallium the next year. Thallium is found in the minerals crooksite (CuThSe), lorandite (TlAsS2) and hutchinsonite ((Pb, Tl)2As5S9), but is usually obtained as a byproduct of the production of sulfuric acid or as a byproduct of refining zinc or lead.
From Greek thallos, meanin a green shoot or twig. Thallium was discovered spectroscopically in 1861 by Crookes. The element was named after the beautiful green spectral line, which identified the element. The metal was isolated both by Crookes and by Lamy in 1862 at about the same time.
Pure thallium is a very soft, heavy metal with a fresh silvery luster. It tarnishes readily in air, developing a dull gray oxide coating. It is malleable enough to be cut with a knife and has a relatively low melting point for a metal.
Current uses are limited by toxicity and regulation. Thallium is used in some specialty infrared optical materials, low-melting glasses, and semiconductor or detector research. Thallium-201 is an important medical radioisotope for diagnostic imaging of cardiac perfusion. Historical uses included rodenticides, insecticides, and depilatory agents, but these were abandoned or tightly restricted in many countries because of poisoning risks.
There are no uses for metallic thallium since pure thallium quickly combines with oxygen and water vapor from the atmosphere, forming a black, powdery substance. Thallium, used in conjunction with sulfur or selenium and arsenic, forms low melting glass. Thallium sulfate (Tl2SO4), an odorless, tasteless thallium compound, was once used as a rat and ant poison, although it has been banned from household use in the United States since 1974. Thallium sulfide (Tl2S), thallium iodide (TlI) and thallium bromide (TlBr) are all compounds used in devices to detect infrared radiation.
Thallium sulfate has been widely employed as a rodenticide and ant killer. It is odorless and tasteless, giving no warning of its presence. Its use, however, has been prohibited in the U.S. since 1975 as a household insecticide and rodenticide. The electrical conductivity of thallium sulfide changes with exposure to infrared light, and this compound is used in photocells. Thallium bromide-iodide crystals have been used as infrared optical materials. Thallium has been used, with sulfur or selenium and arsenic, to produce low melting glasses with become fluid between 125 and 150C. These glasses have properties at room temperatures similar to ordinary glasses and are said to be durable and insoluble in water. Thallium oxide has been used to produce glasses with a high index of refraction, and is used in the manufacture of photo cells. Thallium has been used in treating ringworm and other skin infections; however, its use has been limited because of the narrow margin between toxicity and therapeutic benefits.
Isotopes in Earth/Planetary Science
Because molecules, atoms, and ions of the stable isotopes of thallium possess slightly different physical and chemical properties, they commonly will be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. There are substantial variations in the isotopic abundances of thallium in natural terrestrial materials (Fig. IUPAC.81.1). These variations are useful in investigating the origin of substances and studying environmental, hydrological, and geological processes [538] M. Rehkamper, M. Frank, J. R. Hein, D. Porcelli, A. Halliday, J. Ingri, V. Liebetrau. Earth. Planet. Sci. Lett.197, 65 (2002).. The isotope-amount ratio n(205Tl)/n(203Tl) has been used to study how trace metals are transported and distributed in hydrothermal fluids [538] M. Rehkamper, M. Frank, J. R. Hein, D. Porcelli, A. Halliday, J. Ingri, V. Liebetrau. Earth. Planet. Sci. Lett.197, 65 (2002).. The n(205Tl)/n(203Tl) ratio has also been used to study the cycling, distribution, and behavior of thallium in the marine environment [538] M. Rehkamper, M. Frank, J. R. Hein, D. Porcelli, A. Halliday, J. Ingri, V. Liebetrau. Earth. Planet. Sci. Lett.197, 65 (2002)..
Isotopes in Medicine
201Tl scintigraphy is used to detect coronary artery disease [539] G. A. Beller, B. L. Zaret. Circulation101, 1465 (2000).. Imaging of 201Tl (with a half-life of 3 days), can be used for exercise perfusion tests of the myocardium (muscular tissue of the heart), which determine damage to the heart caused by a heart attack or by heart disease (Fig. IUPAC.81.2) [539] G. A. Beller, B. L. Zaret. Circulation101, 1465 (2000)..
Isotopes Used as a Source of Radioactive Isotope(s)
203Tl is used in the production of 201Tl via the 203Tl (p, 3 n) 201Pb reaction, which is followed by a subsequent electron capture decay reaction of 201Pb to finally yield 201Tl. 205Tl is used as an alternative target in the production of 201Tl.
Thallium chemistry is dominated by thallium(I), Tl⁺, and thallium(III), Tl³⁺, with Tl⁺ usually more stable in aqueous and many solid-state compounds. Representative thallium(I) compounds include thallium(I) sulfate, Tl₂SO₄, thallium(I) nitrate, TlNO₃, and thallium(I) chloride, TlCl. Thallium(III) oxide, Tl₂O₃, and thallium(III) chloride, TlCl₃, are stronger oxidizing or less stable species. Mixed thallium compounds occur in chalcogenide and halide materials used for optical and electronic studies.
See more information at the Thallium compound page.
Thallium and soluble thallium compounds are highly toxic by ingestion, inhalation, or skin exposure. Tl⁺ can interfere with potassium-dependent biological processes, and poisoning may have delayed neurological, gastrointestinal, and hair-loss symptoms. Dusts, fumes, and soluble salts are the main occupational hazards. Radioisotopes such as thallium-201 add external and internal radiation hazards that are isotope- and activity-dependent.
The element and its compounds are toxic and should be handled carefully. Contact of the metal with skin is dangerous, and when melting the metal adequate ventilation should be provided. Exposure to thallium (soluble compounds) - skin, as Tl, should not exceed 0.1 mg/m3 (8-hour time-weighted average - 40-hour work week). Thallium is suspected of carcinogenic potential for man.
Thallium occurs naturally at low concentrations, commonly associated with potassium minerals, sulfide ores, and some coals. Mining, smelting, cement production, and coal combustion can mobilize it locally. In the environment, Tl⁺ is relatively mobile in some waters and can be taken up by plants because of its chemical similarity to K⁺. It has no known beneficial biological role and can be a concern near contaminated industrial sites.
Thallium is not mined as a primary product. It is recovered mainly from flue dusts, residues, and by-product streams generated during refining of zinc, lead, copper, and other sulfide ores. Demand is small and specialized, with toxicity limiting broader applications and encouraging substitution. Supply can therefore depend more on base-metal processing practices, regulatory controls, and purification capacity than on dedicated thallium mining. Recycling is limited to particular industrial or research materials.
Thallium occurs in crooksite, lorandite, and hutchinsonite. It is also present in pyrites and is recovered from the roasting of this ore in connection with the production of sulfuric acid. It is also obtained from the smelting of lead and zinc ores. Extraction is somewhat complex and depends on the source of the thallium. Manganese nodules, found on the ocean floor, contain thallium.
Thallium is a heavy, rare element in cosmic terms. Its stable isotopes, ²⁰³Tl and ²⁰⁵Tl, are produced by neutron-capture processes in earlier generations of stars, with contributions from both slow and rapid neutron-capture pathways. It is not a major rock-forming element, but on planets it can concentrate in sulfide phases and volatile-rich geochemical reservoirs.
- Thallium was discovered by its bright green spectral line, which inspired its name from the Greek word for a green shoot
- Fresh thallium can be cut easily, but the exposed surface dulls quickly in air
- Tl⁺ is close enough in behavior to K⁺ to enter some biological potassium pathways
- Thallium(I) sulfate, Tl₂SO₄, was once used as a rodenticide before its toxicity led to severe restrictions
- Natural thallium consists chiefly of two stable isotopes, ²⁰³Tl and ²⁰⁵Tl
画像
性質
物理的性質
- 原子半径（経験値）
- 190 pm 全元素の原子半径（経験値）を比較 →
- 共有結合半径
- 145 pm 全元素の共有結合半径を比較 →
- ファンデルワールス半径
- 196 pm 全元素のファンデルワールス半径を比較 →
- 金属半径
- 144 pm 全元素の金属半径を比較 →
- 密度
- 1.18 × 104 kg/m³ 全元素の密度を比較 →
- モル体積
- 0.0172 L/mol
- 標準温度・圧力（STP）での相
- 固体 全元素の標準温度・圧力（STP）での相を比較 →
- 融点
- 303.85 °C 全元素の融点を比較 →
- 沸点
- 1472.85 °C 全元素の沸点を比較 →
- 熱伝導率
- 46.1 W/(m·K) 全元素の熱伝導率を比較 →
- 比熱容量
- 0.129 J/(g·K) 全元素の比熱容量を比較 →
- モル熱容量
- 26.32 J/(mol·K) 全元素のモル熱容量を比較 →
- 結晶構造
- 六方最密充填構造 全元素の結晶構造を比較 →
化学的性質
- 電気陰性度（Pauling）
- 1.62 全元素の電気陰性度（Pauling）を比較 →
- 電気陰性度（Allen）
- 1.789
- 電子親和力
- 0.377 eV
- 第1イオン化エネルギー
- 6.108287 eV 全元素の第1イオン化エネルギーを比較 →
- 第2イオン化エネルギー
- 20.42837 eV 全元素の第2イオン化エネルギーを比較 →
- 第3イオン化エネルギー
- 29.852103 eV 全元素の第3イオン化エネルギーを比較 →
- 第4イオン化エネルギー
- 51.140176 eV 全元素の第4イオン化エネルギーを比較 →
- 第5イオン化エネルギー
- 62.600215 eV 全元素の第5イオン化エネルギーを比較 →
- 酸化数
- −5, −2, −1, +1, +2, +3 全元素の酸化数を比較 →
- 価電子
- 3 全元素の価電子を比較 →
- 電子配置
- [Xe] 6s2 4f14 5d10 6p1
熱力学的性質
- 融解熱
- 0.04290822 eV 全元素の融解熱を比較 →
- 蒸発熱
- 1.71011 eV 全元素の蒸発熱を比較 →
- 昇華熱
- 1.888376 eV
- 原子化熱
- 1.888376 eV
- 原子化エンタルピー
- 1.888376 eV
原子核
- 陽子数
- 81 全元素の陽子数を比較 →
- 中性子数
- 124 全元素の中性子数を比較 →
- 既知の同位体
- 43 全元素の既知の同位体を比較 →
- 安定同位体
- 2 全元素の安定同位体を比較 →
- 最も安定な同位体
- Tl-205
- 発見年
- 1861
存在度
- 存在度（地殻）
- 0.85 mg/kg 全元素の存在度（地殻）を比較 →
- 存在度（海洋）
- 1.9 × 10−5 mg/L 全元素の存在度（海洋）を比較 →
結晶構造
- 格子定数a
- 346 pm
電子構造
- 各電子殻の電子数
- 2, 8, 18, 32, 18, 3 全元素の各電子殻の電子数を比較 →
識別子
- CAS登録番号
- 7440-28-0 全元素のCAS登録番号を比較 →
- 項記号
- 2P°1/2
- InChI
- InChI=1S/Tl
- InChI Key
- BKVIYDNLLOSFOA-UHFFFAOYSA-N
電子配置 測定値
Tl: 4f¹⁴ 5d¹⁰ 6s² 6p¹[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p¹原子モデル
同位体によって中性子数、質量、安定性は変わりますが、中性原子の電子配置は変わりません。
模式的な原子モデルです。実際の縮尺とは異なります。
原子の指紋
発光／吸収スペクトル
同位体分布
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 |
|---|---|---|---|
| 203 安定 | 202.9723446 ± 0.0000014 | 29.5200% | 安定 |
| 205 安定 | 204.9744278 ± 0.0000014 | 70.4800% | 安定 |
相／状態
理由: 融点（303.85 °C）より278.9 °C低い
模式図、実際の縮尺とは異なります
相転移点
相転移エネルギー
融点で1 molを融解させるのに必要なエネルギー
沸点で1 molを蒸発させるのに必要なエネルギー
昇華点で1 molを昇華させるのに必要なエネルギー
密度
標準条件下
標準条件下
原子スペクトル
全81件中10件を表示しています。 イオンの電荷の昇順で並べています。
スペクトル線データの収録状況 ?
| イオン | 電荷 | スペクトル線の総数 | 遷移確率 | 準位の表記 |
|---|---|---|---|---|
| Tl I | 0 | 65 | 25 | 11 |
| Tl II | +1 | 82 | 3 | 7 |
| Tl III | +2 | 22 | 0 | 0 |
| Tl IV | +3 | 35 | 0 | 0 |
準位データの収録状況 ?
| イオン | 電荷 | 準位 |
|---|---|---|
| Tl I | 0 | 70 |
| Tl II | +1 | 82 |
| Tl III | +2 | 109 |
| Tl IV | +3 | 44 |
| Tl V | +4 | 2 |
| Tl VI | +5 | 2 |
| Tl VII | +6 | 2 |
| Tl VIII | +7 | 2 |
| Tl IX | +8 | 2 |
| Tl X | +9 | 2 |
イオン半径
| 電荷 | 配位 | スピン | 半径 |
|---|---|---|---|
| +1 | 6 | データなし | 150 pm |
| +1 | 8 | データなし | 159 pm |
| +1 | 12 | データなし | 170 pm |
| +3 | 4 | データなし | 75 pm |
| +3 | 6 | データなし | 88.5 pm |
| +3 | 8 | データなし | 98 pm |
化合物
同位体 (2)
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 | 崩壊形式 | |
|---|---|---|---|---|---|
| 203 安定 | 202.9723446 ± 0.0000014 | 29.5200% ± 0.0100% | 安定 | stable | |
| 205 安定 | 204.9744278 ± 0.0000014 | 70.4800% ± 0.0100% | 安定 | stable |
詳細な性質
共有結合半径（詳細）
- 共有結合半径（Pyykkö）
- 144 pm
- 共有結合半径（Pyykkö、二重結合）
- 142 pm
- 共有結合半径（Pyykkö、三重結合）
- 150 pm
- 共有結合半径（Bragg）
- 190 pm
ファンデルワールス半径
- Bondi
- 196 pm
- Batsanov
- 220 pm
- Alvarez
- 247 pm
- UFF
- 434.7 pm
- MM3
- 259 pm
原子半径と金属半径
- 原子半径（Rahm）
- 242 pm
- 金属半径（C12）
- 160 pm
番号付けの尺度
- Mendeleev
- 85
- Pettifor
- 78
- Glawe
- 81
電気陰性度の尺度
- Ghosh
- 0
- Miedema
- 4
- Gunnarsson–Lundqvist
- 3
- Robles–Bartolotti
- 2
分極率と分散
- 双極子分極率
- 50 a.u.
- 双極子分極率（不確かさ）
- 2 a.u.
- C₆ (Gould–Bučko)
- 509 Ha·Bohr6
ミーデマパラメータ
- ミーデマモル体積
- 17.23 cm3/mol
- ミーデマ電子密度
- 1
相転移と同素体
| 融点 | 577.15 K |
| 沸点 | 1746.15 K |
酸化数の分類
専門参考データ
遮蔽定数 (15)
| n | 軌道 | σ |
|---|---|---|
| 1 | s | 1.5591 |
| 2 | p | 4.5138 |
| 2 | s | 21.3158 |
| 3 | d | 13.4658 |
| 3 | p | 22.6335 |
| 3 | s | 23.5809 |
| 4 | d | 37.6112 |
| 4 | f | 38.1324 |
| 4 | p | 35.7832 |
| 4 | s | 34.9212 |
結晶半径の詳細 (6)
| 電荷 | CN | スピン | rcrystal (pm) | 由来 |
|---|---|---|---|---|
| 1 | VI | 164 | from r^3 vs V plots, | |
| 1 | VIII | 173 | from r^3 vs V plots, | |
| 1 | XII | 184 | from r^3 vs V plots, estimated, | |
| 3 | IV | 89 | ||
| 3 | VI | 102.5 | from r^3 vs V plots, | |
| 3 | VIII | 112 | calculated, |
同位体の崩壊形式 (69)
| 同位体 | モード | 強度 |
|---|---|---|
| 176 | p | 100% |
| 176 | A | — |
| 176 | B+ | — |
| 177 | A | 73% |
| 177 | p | — |
| 178 | A | 62% |
| 178 | B+ | 38% |
| 178 | B+SF | 0.1% |
| 179 | A | 60% |
| 179 | B+ | — |
X線散乱因子 (516)
| エネルギー (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1.80392 |
| 10.1617 | — | 1.75555 |
| 10.3261 | — | 1.69589 |
| 10.4931 | — | 1.59546 |
| 10.6628 | — | 1.46625 |
| 10.8353 | — | 1.39341 |
| 11.0106 | — | 1.31349 |
| 11.1886 | — | 1.20783 |
| 11.3696 | — | 1.13261 |
| 11.5535 | — | 1.07387 |
追加データ
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
8.5×10-1 milligrams per kilogram
参考文献 (1)
- [5] Thallium https://education.jlab.org/itselemental/ele081.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
1.9×10-5 milligrams per liter
参考文献 (1)
- [5] Thallium https://education.jlab.org/itselemental/ele081.html
Sources
Sources of this element.
Thallium occurs in crooksite, lorandite, and hutchinsonite. It is also present in pyrites and is recovered from the roasting of this ore in connection with the production of sulfuric acid. It is also obtained from the smelting of lead and zinc ores. Extraction is somewhat complex and depends on the source of the thallium. Manganese nodules, found on the ocean floor, contain thallium.
参考文献 (1)
- [6] Thallium https://periodic.lanl.gov/81.shtml
参考文献
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Thallium.
The element property data was retrieved from publications.