Barium (Ba)
alkaline-earth-metalSolid
標準原子量
137.327 u電子配置
[Xe] 6s2融点
726.85 °C沸点
1896.85 °C密度
3620 kg/m³酸化数
+1, +2電気陰性度（Pauling）
0.89第1イオン化エネルギー
5.211665 eV発見年
1808原子半径
215 pm詳細
Barium is a soft alkaline earth metal, below strontium and above radium in group 2. It is highly reactive, forms Ba²⁺ compounds almost exclusively, and is not found free in nature. Its most important minerals are barite, barium sulfate, and witherite, barium carbonate. The element is technologically significant less as a metal than through dense, insoluble, or optically useful compounds.
Barium is a metallic element, soft, and when pure is silvery white; it belongs to the alkaline earth group, chemically resembling calcium. The metal oxidizes very easily and should be kept under petroleum or other suitable oxygen-free liquids to exclude air. It is decomposed by water or alcohol.
Barium was first isolated by Sir Humphry Davy, an English chemist, in 1808 through the electrolysis of molten baryta (BaO). Barium is never found free in nature since it reacts with oxygen in the air, forming barium oxide (BaO), and with water, forming barium hydroxide (Ba(OH)2) and hydrogen gas (H2). Barium is most commonly found as the mineral barite (BaSO4) and witherite (BaCO3) and is primarily produced through the electrolysis of barium chloride (BaCl2).
From the Greek word barys, heavy. Baryta was distinguished from lime by Scheele in 1774; the element was discovered by Sir Humphrey Davy in 1808.
Pure barium is a silvery-white to pale yellow metal when freshly cut. It tarnishes rapidly in air as oxide, nitride, and peroxide-containing surface films form. The metal is soft, relatively dense for an alkaline earth metal, and is normally stored under oil or inert gas.
Elemental barium has limited direct use because of its reactivity. It has been used as a getter in vacuum tubes, where it removes residual gases by forming stable compounds. Barium compounds have broader roles: barium sulfate (BaSO₄) is used as a radiopaque contrast material and as an inert filler; barium titanate (BaTiO₃) is a ferroelectric ceramic used in capacitors and related devices; and barium nitrate (Ba(NO₃)₂) and barium chlorate (Ba(ClO₃)₂) can produce green colors in pyrotechnics.
Barium is used as a getter, a material that combines with and removes trace gases from vacuum tubes.
Barium sulfate (BaSO4), a common barium compound, is used as a filler for rubber, plastics and resins. It can be combined with zinc oxide (ZnO) to make a white pigment known as lithophone or with sodium sulfate (Na2SO4) to make another white pigment known as blanc fixe. Stones made from impure barium sulfate glow when exposed to light and will glow in the dark for up to six years if intensely heated in the presence of charcoal. These stones, known as Bologna stones, were discovered near Bologna, Italy in the early 1500s and were thought to possess magical properties by alchemists. Although all barium compounds are poisonous, barium sulfate can be safely ingested since it does not dissolve in water. It is also a good absorber of X-rays and, when swallowed, can be used to produce X-ray images of the intestinal tract.
Barium carbonate (BaCO3), another common barium compound, is used in the manufacture of ceramics and some types of glass. It is a component in clay slurries used in drilling oil wells. Barium carbonate is used to purify some chemical solutions and is the primary base material for the manufacture of other barium compounds.
Barium forms several other useful compounds. Barium nitrate (Ba(NO3)2) burns with a bright green color and is used in signal flares and fireworks. Barium chloride (BaCl) is used as a water softener. Barium oxide (BaO) easily absorbs moisture and is used as a desiccant. Barium peroxide (BaO2) forms hydrogen peroxide (H2O2) when it is mixed with water and is used as a bleaching agent that activates when wet. Barium titanate (BaTiO3) is used as a dielectric material in capacitors. Barium ferrite (BaO·6Fe2O3) is used to make magnets.
Barium-137m, a radioactive form of barium produced by the decay of cesium-137, has a relatively short half-life and is commonly used in high school and college physics half-life determination experiments.
The metal is used as a "getter" in vacuum tubes. The most important compounds are the peroxide, chloride, sulfate, carbonate, nitrate, and chlorate. Lithopone, a pigment containing barium sulfate and zinc sulfide, has good covering power, and does not darken in the presence of sulfides. The sulfate, as permanent white is also used in paint, in X-ray diagnostic work, and in glassmaking. Barite is extensively used as a weighing agent in oil well drilling fluids, and is used in making rubber. The carbonate has been used as a rat poison, while the nitrate and chlorate give colors in pyrotechnics. The impure sulfide phosphoresces after exposure to the light. All barium compounds that are water or acid soluble are poisonous. Naturally occurring barium is a mixture of seven stable isotopes. Twenty two other radioactive isotopes are known to exist.
Isotopes in Earth/Planetary Science
Because molecules, atoms, and ions of the stable isotopes of barium possess slightly different physical and chemical properties, they can be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. von Allmen et al. [410] K. v. Allmen, M. E. Böttcher, E. Samankassou, T. F. Nägler. Chem. Geol.277, 70 (2010). observed barium isotopic fractionation in the global barium cycle (Fig. IUPAC.56.1).
High-precision barium isotope measurements reveal differences of up to 25 parts per million in the isotope-amount ratio n(137Ba)/n(136Ba) and 60 parts per million in the n(138Ba)/n(136Ba) ratio between chondrites and the Earth. These differences probably arose from incomplete mixing of nucleosynthetic material in the solar nebula. Barium isotopes may be the decay products of now-extinct 135Cs (with a half-life of about 1.6×106 years), which is thought to be a nucleosynthetic component. Chondritic meteorites have a slight excess of supernova-derived material as compared to Earth, demonstrating that the solar nebula was not perfectly homogenized upon formation (Fig. IUPAC.56.1) [411] M. C. Ranen, S. B. Jacobsen. Science314, 809 (2006)., [412] H. Hidaka, Y. Ohta, S. Yoneda. Earth. Planet. Sci. Lett.214, 455 (2003)., [413] S. B. Jacobsen, M. C. Ranen. Geochim. Cosmochim. Acta70, A286 (2006)..
Barium chemistry is dominated by the +2 oxidation state and by large, mostly ionic Ba²⁺ salts. Barium oxide (BaO) is a basic oxide, while barium hydroxide (Ba(OH)₂) is a strong base. Barium sulfate (BaSO₄) is exceptionally insoluble, a property central to analytical sulfate tests and medical contrast use. Barium carbonate (BaCO₃), barium chloride (BaCl₂), and barium nitrate (Ba(NO₃)₂) are important laboratory or industrial salts, but soluble barium salts are toxic. Mixed oxides such as barium titanate (BaTiO₃) are important functional ceramics.
See more information at the Barium compound page.
Metallic barium reacts with moisture and can ignite or release hydrogen, so it is handled as an air-sensitive reactive metal. Soluble barium compounds, including barium chloride (BaCl₂) and barium nitrate (Ba(NO₃)₂), are poisonous because Ba²⁺ interferes with potassium ion transport and muscle function. Barium sulfate (BaSO₄) is far less hazardous by ingestion because of its very low solubility, provided it is free of soluble barium impurities.
Barium occurs naturally in crustal rocks, especially as barite, barium sulfate (BaSO₄), and witherite, barium carbonate (BaCO₃). Its mobility depends strongly on sulfate, carbonate, and pH conditions; insoluble sulfate tends to immobilize it, while soluble salts can enter groundwater locally. Barium is not an essential nutrient for most organisms, and elevated soluble barium can be harmful to aquatic and terrestrial life.
Barium is supplied mainly through mining and processing of barite, barium sulfate (BaSO₄), with smaller contributions from other barium minerals where available. Much barite is consumed directly after grinding, especially where high density and chemical inertness are useful, rather than being converted to metal. Barium metal is made by reducing barium compounds under controlled conditions and is a small specialty product. Demand is driven by drilling fluids, fillers, ceramics, glass, pyrotechnics, and chemical manufacture; substitution is possible in some uses but difficult where density, insolubility, or specific electronic properties are required.
It is found only in combination with other elements, chiefly with sulfate and carbonate and is prepared by electrolysis of the chloride.
Barium is heavier than iron and is formed mainly by neutron-capture processes in stars, especially the slow s-process in evolved stars and the rapid r-process in explosive or merger environments. Its spectral lines are important in stellar abundance studies, and barium enrichment in some stars records past nucleosynthesis and mass transfer. In planetary materials it is a trace lithophile element concentrated in minerals and melts rather than metallic cores.
- Barium sulfate is so insoluble that it can be swallowed for X-ray imaging despite barium ion toxicity.
- The name comes from Greek barys, meaning heavy, reflecting the high density of barite.
- Barium flame tests give an apple-green color, though impurities can mask it.
- Natural barium is a mixture of several stable isotopes, with ¹³⁸Ba the most abundant.
- Barium titanate was one of the first widely important ferroelectric ceramics.
画像
性質
物理的性質
- 原子半径（経験値）
- 215 pm 全元素の原子半径（経験値）を比較 →
- 共有結合半径
- 215 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
- 268 pm 全元素のファンデルワールス半径を比較 →
- 金属半径
- 198 pm 全元素の金属半径を比較 →
- 密度
- 3620 kg/m³ 全元素の密度を比較 →
- モル体積
- 0.039 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
- 726.85 °C 全元素の融点を比較 →
- 沸点
- 1896.85 °C 全元素の沸点を比較 →
- 比熱容量
- 0.204 J/(g·K) 全元素の比熱容量を比較 →
- モル熱容量
- 28.07 J/(mol·K) 全元素のモル熱容量を比較 →
- 結晶構造
- 体心立方構造 全元素の結晶構造を比較 →
化学的性質
- 電気陰性度（Pauling）
- 0.89 全元素の電気陰性度（Pauling）を比較 →
- 電気陰性度（Allen）
- 0.881
- 電子親和力
- 0.1447 eV
- 第1イオン化エネルギー
- 5.211665 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
- 10.00386 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
- 35.843923 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
- 47.000162 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
- 58.0002 eV 全元素の第5イオン化エネルギーを比較 →
- 酸化数
- +1, +2 全元素の酸化数を比較 →
- 価電子
- 2 全元素の価電子を比較 →
- 電子配置
- [Xe] 6s2
熱力学的性質
- 融解熱
- 0.07939058 eV 全元素の融解熱を比較 →
- 蒸発熱
- 1.461367 eV 全元素の蒸発熱を比較 →
- 昇華熱
- 1.865575 eV
- 原子化熱
- 1.865575 eV
- 原子化エンタルピー
- 1.856247 eV
原子核
- 陽子数
- 56 全元素の陽子数を比較 →
- 中性子数
- 82 全元素の中性子数を比較 →
- 既知の同位体
- 42 全元素の既知の同位体を比較 →
- 安定同位体
- 5 全元素の安定同位体を比較 →
- 最も安定な同位体
- Ba-138
- 発見年
- 1808
存在度
- 存在度（地殻）
- 425 mg/kg 全元素の存在度（地殻）を比較 →
- 存在度（海洋）
- 0.013 mg/L 全元素の存在度（海洋）を比較 →
結晶構造
- 格子定数a
- 502 pm
電子構造
- 各電子殻の電子数
- 2, 8, 18, 18, 8, 2 全元素の各電子殻の電子数を比較 →
識別子
- CAS登録番号
- 7440-39-3 全元素のCAS登録番号を比較 →
- 項記号
- 1S0
- InChI
- InChI=1S/Ba
- InChI Key
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N
電子配置 測定値
Ba: 6s²[Xe] 6s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 6s²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 |
|---|---|---|---|
| 134 安定 | 133.90450818 ± 0.0000003 | 2.4170% | 安定 |
| 135 安定 | 134.90568838 ± 0.00000029 | 6.5920% | 安定 |
| 136 安定 | 135.90457573 ± 0.00000029 | 7.8540% | 安定 |
| 137 安定 | 136.90582714 ± 0.0000003 | 11.2320% | 安定 |
| 138 安定 | 137.905247 ± 0.00000031 | 71.6980% | 安定 |
相／状態
理由: 融点（726.85 °C）より701.9 °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56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 |
|---|---|---|---|---|
| Ba I | 0 | 312 | 109 | 312 |
| Ba II | +1 | 112 | 94 | 112 |
| Ba III | +2 | 535 | 5 | 529 |
| Ba IV | +3 | 42 | 3 | 42 |
| Ba V | +4 | 135 | 0 | 126 |
| Ba VI | +5 | 138 | 0 | 127 |
| Ba VII | +6 | 70 | 0 | 70 |
| Ba VIII | +7 | 141 | 141 | 141 |
| Ba IX | +8 | 110 | 110 | 110 |
| Ba X | +9 | 31 | 31 | 31 |
準位データの収録状況 ?
| イオン | 電荷 | 準位 |
|---|---|---|
| Ba I | 0 | 356 |
| Ba II | +1 | 162 |
| Ba III | +2 | 162 |
| Ba IV | +3 | 34 |
| Ba V | +4 | 52 |
| Ba VI | +5 | 50 |
| Ba VII | +6 | 32 |
| Ba VIII | +7 | 79 |
| Ba IX | +8 | 55 |
| Ba X | +9 | 30 |
イオン半径
| 電荷 | 配位 | スピン | 半径 |
|---|---|---|---|
| +2 | 6 | データなし | 135 pm |
| +2 | 7 | データなし | 138 pm |
| +2 | 8 | データなし | 142 pm |
| +2 | 9 | データなし | 147 pm |
| +2 | 10 | データなし | 152 pm |
| +2 | 11 | データなし | 157 pm |
| +2 | 12 | データなし | 161 pm |
化合物
同位体 (5)
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 | 崩壊形式 | |
|---|---|---|---|---|---|
| 134 安定 | 133.90450818 ± 0.0000003 | 2.4170% ± 0.0180% | 安定 | stable | |
| 135 安定 | 134.90568838 ± 0.00000029 | 6.5920% ± 0.0120% | 安定 | stable | |
| 136 安定 | 135.90457573 ± 0.00000029 | 7.8540% ± 0.0240% | 安定 | stable | |
| 137 安定 | 136.90582714 ± 0.0000003 | 11.2320% ± 0.0240% | 安定 | stable | |
| 138 安定 | 137.905247 ± 0.00000031 | 71.6980% ± 0.0420% | 安定 | stable |
スペクトル線
全92件中50件を表示しています。 初期設定では、強度の測定値があるスペクトル線のみを表示します。
| 波長（nm） | 強度 | 電離段階 | 種類 | 遷移 | 精度 | 出典 | |
|---|---|---|---|---|---|---|---|
| 392.686 nm | 25 | Ba III | emission | 5p5.(2P*<3/2>).6s 2[3/2]* → 5p5.(2P*<3/2>).6p 2[1/2] | 測定値 | NIST | |
| 399.306 nm | 25 | Ba III | emission | 5p5.(2P*<3/2>).6s 2[3/2]* → 5p5.(2P*<3/2>).6p 2[5/2] | 測定値 | NIST | |
| 381.3128 nm | 16 | Ba III | emission | 5p5.(2P*<1/2>).6s 2[1/2]* → 5p5.(2P*<1/2>).4f 2[5/2] | 測定値 | NIST | |
| 469.7428 nm | 15 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[3/2]* → 5p5.(2P*<1/2>).6p 2[1/2] | 測定値 | NIST | |
| 448.1646 nm | 14 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[3/2]* → 5p5.(2P*<3/2>).6p 2[5/2] | 測定値 | NIST | |
| 610.1987 nm | 13 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[3/2]* → 5p5.(2P*<1/2>).4f 2[5/2] | 測定値 | NIST | |
| 389.6957 nm | 12 | Ba III | emission | 5p5.(2P*<3/2>).5d 2[5/2]* → 5p5.(2P*<3/2>).4f 2[3/2] | 測定値 | NIST | |
| 392.723 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5d 2[5/2]* → 5p5.(2P*<3/2>).4f 2[9/2] | 測定値 | NIST | |
| 432.793 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).6s 2[3/2]* → 5p5.(2P*<3/2>).6p 2[1/2] | 測定値 | NIST | |
| 482.0642 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[3/2] → 5p5.(2P*<3/2>).5g 2[5/2]* | 測定値 | NIST | |
| 485.0833 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[3/2] → 5p5.(2P*<3/2>).5g 2[5/2]* | 測定値 | NIST | |
| 496.4038 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[5/2] → 5p5.(2P*<3/2>).5g 2[7/2]* | 測定値 | NIST | |
| 504.9533 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[5/2] → 5p5.(2P*<3/2>).5g 2[7/2]* | 測定値 | NIST | |
| 509.7537 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[7/2] → 5p5.(2P*<3/2>).5g 2[9/2]* | 測定値 | NIST | |
| 513.4529 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[7/2] → 5p5.(2P*<3/2>).5g 2[9/2]* | 測定値 | NIST | |
| 599.7996 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).7d 2[7/2]* | 測定値 | NIST | |
| 637.7094 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[3/2] → 5p5.(2P*<3/2>).7d 2[5/2]* | 測定値 | NIST | |
| 638.3756 nm | 10 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).7d 2[7/2]* | 測定値 | NIST | |
| 438.5824 nm | 9 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[5/2]* → 5p5.(2P*<3/2>).6p 2[5/2] | 測定値 | NIST | |
| 464.6207 nm | 9 | Ba III | emission | 5p5.(2P*<3/2>).5d 2[5/2]* → 5p5.(2P*<3/2>).4f 2[3/2] | 測定値 | NIST | |
| 542.699 nm | 9 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[5/2]* → 5p5.(2P*<3/2>).6p 2[5/2] | 測定値 | NIST | |
| 491.7171 nm | 8 | Ba III | emission | 5p5.(2P*<1/2>).5f 2[7/2] → 5p5.(2P*<1/2>).5g 2[9/2]* | 測定値 | NIST | |
| 494.5436 nm | 8 | Ba III | emission | 5p5.(2P*<1/2>).5f 2[5/2] → 5p5.(2P*<1/2>).5g 2[7/2]* | 測定値 | NIST | |
| 495.2914 nm | 8 | Ba III | emission | 5p5.(2P*<1/2>).5f 2[5/2] → 5p5.(2P*<1/2>).5g 2[7/2]* | 測定値 | NIST | |
| 496.3235 nm | 8 | Ba III | emission | 5p5.(2P*<1/2>).5f 2[7/2] → 5p5.(2P*<1/2>).5g 2[9/2]* | 測定値 | NIST | |
| 503.3498 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).5g 2[5/2]* | 測定値 | NIST | |
| 503.7341 nm | 8 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[3/2]* → 5p5.(2P*<1/2>).6p 2[1/2] | 測定値 | NIST | |
| 590.0288 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[9/2] → 5p5.(2P*<3/2>).7d 2[7/2]* | 測定値 | NIST | |
| 601.6412 nm | 8 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[3/2]* → 5p5.(2P*<1/2>).6p 2[3/2] | 測定値 | NIST | |
| 603.6589 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[5/2] → 5p5.(2P*<3/2>).7d 2[7/2]* | 測定値 | NIST | |
| 607.7807 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).6s 2[3/2]* → 5p5.(2P*<3/2>).4f 2[3/2] | 測定値 | NIST | |
| 627.0084 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[3/2] → 5p5.(2P*<3/2>).7d 2[5/2]* | 測定値 | NIST | |
| 652.6166 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).8s 2[3/2]* | 測定値 | NIST | |
| 709.5497 nm | 8 | Ba III | emission | 5p5.(2P*<3/2>).6s 2[3/2]* → 5p5.(2P*<3/2>).4f 2[3/2] | 測定値 | NIST | |
| 519.6426 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).5g 2[7/2]* | 測定値 | NIST | |
| 552.8138 nm | 7 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[3/2]* → 5p5.(2P*<3/2>).6p 2[1/2] | 測定値 | NIST | |
| 574.0413 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[3/2] → 5p5.(2P*<3/2>).7d 2[7/2]* | 測定値 | NIST | |
| 579.8254 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[5/2] → 5p5.(2P*<3/2>).7d 2[5/2]* | 測定値 | NIST | |
| 585.9192 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).7d 2[5/2]* | 測定値 | NIST | |
| 588.1879 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[9/2] → 5p5.(2P*<3/2>).7d 2[7/2]* | 測定値 | NIST | |
| 598.3721 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[1/2] → 5p5.(2P*<3/2>).7d 2[1/2]* | 測定値 | NIST | |
| 658.3333 nm | 7 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[3/2] → 5p5.(2P*<3/2>).7d 2[3/2]* | 測定値 | NIST | |
| 565.8601 nm | 6 | Ba III | emission | 5p5.(2P*<1/2>).5d 2[5/2]* → 5p5.(2P*<3/2>).4f 2[7/2] | 測定値 | NIST | |
| 569.7415 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[3/2] → 5p5.(2P*<3/2>).7d 2[3/2]* | 測定値 | NIST | |
| 571.6614 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[1/2] → 5p5.(2P*<3/2>).7d 2[3/2]* | 測定値 | NIST | |
| 572.6169 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[3/2] → 5p5.(2P*<3/2>).7d 2[3/2]* | 測定値 | NIST | |
| 581.3545 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[3/2] → 5p5.(2P*<3/2>).7d 2[1/2]* | 測定値 | NIST | |
| 607.6665 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).5f 2[7/2] → 5p5.(2P*<3/2>).7d 2[5/2]* | 測定値 | NIST | |
| 613.1372 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[5/2] → 5p5.(2P*<3/2>).7d 2[1/2]* | 測定値 | NIST | |
| 640.614 nm | 6 | Ba III | emission | 5p5.(2P*<3/2>).7p 2[1/2] → 5p5.(2P*<3/2>).7d 2[3/2]* | 測定値 | NIST |
詳細な性質
共有結合半径（詳細）
- 共有結合半径（Pyykkö）
- 196 pm
- 共有結合半径（Pyykkö、二重結合）
- 161 pm
- 共有結合半径（Pyykkö、三重結合）
- 149 pm
- 共有結合半径（Bragg）
- 210 pm
ファンデルワールス半径
- Truhlar
- 268 pm
- Batsanov
- 270 pm
- Alvarez
- 303 pm
- UFF
- 370.3 pm
- MM3
- 307 pm
原子半径と金属半径
- 原子半径（Rahm）
- 293 pm
- 金属半径（C12）
- 222 pm
番号付けの尺度
- Mendeleev
- 9
- Pettifor
- 14
- Glawe
- 14
電気陰性度の尺度
- Ghosh
- 0
- Miedema
- 2
- Gunnarsson–Lundqvist
- 3
- Robles–Bartolotti
- 2
分極率と分散
- 双極子分極率
- 272 a.u.
- 双極子分極率（不確かさ）
- 10 a.u.
- C₆ (Gould–Bučko)
- 5540 Ha·Bohr6
ミーデマパラメータ
- ミーデマモル体積
- 38.1 cm3/mol
- ミーデマ電子密度
- 1
供給リスクと経済性
- 生産集中度
- 44
- 相対供給リスク
- 8
- 埋蔵量の分布
- 42
- 政治的安定性（最大生産国）
- 24
- 政治的安定性（最大埋蔵国）
- 24
相転移と同素体
| 融点 | 1000.15 K |
| 沸点 | 2118.15 K |
酸化数の分類
専門参考データ
遮蔽定数 (12)
| n | 軌道 | σ |
|---|---|---|
| 1 | s | 1.1139 |
| 2 | p | 4.1904 |
| 2 | s | 14.7532 |
| 3 | d | 13.9757 |
| 3 | p | 18.6836 |
| 3 | s | 18.8444 |
| 4 | d | 32.216 |
| 4 | p | 29.1968 |
| 4 | s | 28.08 |
| 5 | p | 41.1995 |
結晶半径の詳細 (7)
| 電荷 | CN | スピン | rcrystal (pm) | 由来 |
|---|---|---|---|---|
| 2 | VI | 149 | ||
| 2 | VII | 152 | calculated, | |
| 2 | VIII | 156 | ||
| 2 | IX | 161 | ||
| 2 | X | 166 | ||
| 2 | XI | 171 | ||
| 2 | XII | 175 | calculated, |
同位体の崩壊形式 (55)
| 同位体 | モード | 強度 |
|---|---|---|
| 113 | p | — |
| 113 | A | — |
| 114 | B+ | 100% |
| 114 | B+p | 20% |
| 114 | A | 0.9% |
| 114 | 12C | 0% |
| 115 | B+ | 100% |
| 115 | B+p | 15% |
| 116 | B+ | 100% |
| 116 | B+p | 3% |
X線散乱因子 (508)
| エネルギー (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 0.10258 |
| 10.1617 | — | 0.10761 |
| 10.3261 | — | 0.11287 |
| 10.4931 | — | 0.1184 |
| 10.6628 | — | 0.1242 |
| 10.8353 | — | 0.13028 |
| 11.0106 | — | 0.13666 |
| 11.1886 | — | 0.14335 |
| 11.3696 | — | 0.15037 |
| 11.5535 | — | 0.15773 |
追加データ
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
4.25×102 milligrams per kilogram
参考文献 (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
1.3×10-2 milligrams per liter
参考文献 (1)
Sources
Sources of this element.
It is found only in combination with other elements, chiefly with sulfate and carbonate and is prepared by electrolysis of the chloride.
参考文献 (1)
- [6] Barium https://periodic.lanl.gov/56.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 Barium.
The element property data was retrieved from publications.