Actinium (Ac)
actinideSolid
標準原子量
[227]電子配置
[Rn] 7s2 6d1融点
1050.85 °C沸点
3197.85 °C密度
1.007e+4 kg/m³酸化数
+3電気陰性度（Pauling）
1.1第1イオン化エネルギー
5.380235 eV発見年
1899原子半径
195 pm詳細
Actinium is a radioactive actinide metal and the element that gives the actinide series its name. Natural actinium is present only in minute amounts, chiefly as ²²⁷Ac in uranium decay chains. Its chemistry is dominated by the +3 oxidation state and resembles that of lanthanum more than the later, more strongly 5f-influenced actinides. Because all isotopes are radioactive and scarce, most knowledge comes from tracer-scale chemistry rather than ordinary bulk handling.
Actinium-227, a decay product of uranium-235, is a beta emitter with a 21.6-year half-life. Its principal decay products are thorium-227 (18.5-day half-life), radium-223 (11.4-day half-life), and a number of short-lived products including radon, bismuth, polonium, and lead isotopes. In equilibrium with its decay products, it is a powerful source of alpha particles. Actinium metal has been prepared by the reduction of actinium fluoride with lithium vapor at about 1100 to 1300-degrees C. The chemical behavior of actinium is similar to that of the rare earths, particularly lanthanum. Purified actinium comes into equilibrium with its decay products at the end of 185 days, and then decays according to its 21.6-year half-life. It is about 150 times as active as radium, making it of value in the production of neutrons.
In April of 2012, Los Alamos National Laboratory announced a new medical isotope project that shows promise for rapidly producing major quantities of a new cancer-treatment agent, actinium 225 (Ac-225). Both a press release and a video are available.
Actinium was discovered in 1899 by André-Louis Debierne, a French chemist, while experimenting with new methods of separating rare earth oxides. Friedrich Otto Giesel independently discovered actinium in 1902. Actinium is a rare element that is present in uranium ores in tiny amounts, but it is usually cheaper and easier to create actinium when it is needed by bombarding radium with neutrons in a nuclear reactor.
Actinium's most stable isotope, actinium-227, has a half-life of 21.77 years. It decays into francium-223 through alpha decay or into thorium-227 through beta decay.
From the Greek aktis, aktinos, meaning beam or ray. Discovered by Andre Debierne in 1899 and independently by F. Giesel in 1902. Occurs naturally in association with uranium minerals.
A freshly prepared macroscopic sample has rarely been available. Metallic actinium is described as silvery, but its bulk appearance and many physical properties are not as well characterized as those of common metals. It is expected to tarnish rapidly in air and to be self-luminous in the dark from intense radioactivity exciting surrounding materials.
Actinium has no broad commercial use as an elemental material. ²²⁵Ac is important in research and limited clinical development for targeted alpha therapy, where it is attached to carrier molecules intended to deliver alpha-emitting decay products to diseased cells. ²²⁷Ac has been used as a source for generating ²²⁷Th and other decay-chain nuclides, and actinium isotopes are used in radiochemical research, detector calibration, and studies of actinide separation chemistry. Proposed neutron-source uses with light-element targets are historically noted but are not a major present application.
Actinium has no significant commercial applications, although it is used in the production of neutrons.
Isotopes in Earth/Planetary Science
227Ac (with a half-life of 21.77 years) has been used as a tracer of deep-sea mixing in the oceans. By determining concentrations of 227Ac in a water column, scientists can study the rates and patterns of mixing and other vertical exchange processes [583] W. Geibert, M. M. Rutgers van der Loeff, C. Hanfland, H. J. Dauelsberg. Earth. Planet. Sci. Lett.198, 147 (2002).. As a product of the 235U decay chain, 227Ac and other radioisotopes have been used to determine information about the movement of fluids in mid-oceanic ridges and basaltic melts [584] D. McKenzie. Chem. Geol.162, 81 (2000)., [585] W. S. Moore, W. Ussler III, C. K. Paull. Mar. Chem.109, 421 (2008)..
Isotopes in Medicine
225Ac (with a half-life of 10 days) can be used in cancer treatments (Fig. IUPAC.89.1). The isotope is attached to a chelating agent (a substance that can form multiple bonds to a single metal ion) and delivered to the problem site. The emissions of alpha particles from actinium and its daughter products cause tumor death [586] M. R. McDevitt, D. Ma, L. T. Lai, J. Simon, P. Borchardt, R. K. Frank, K. Wu, V. Pellegrini, M. J. Curcio, M. Miederer, N. H. Bander, D. A. Scheinberg. Science294, 1537 (2001).. 225Ac in a series of alpha decays produces 213Bi (with a half-life of 0.76 h), which is also used for radioimmunotherapy [587] D. Ma, M. R. McDevitt, R. D. Finn, D. A. Scheinberg. Appl. Radiat. Isot.55, 667 (2001)..
Isotopes Used as a Source of Radioactive Isotope(s)
225Ac, which is a pure alpha emitter, is used to produce 213Bi with an 225Ac/ 213Bi radionuclide generator (Fig. IUPAC.89.2). 213Bi is a mixed alpha and beta emitter. The primary mode of decay is by beta emission to the very short-lived, alpha emitter 213Po. The 8.4 MeV alpha particle emitted by 213Po has a path length of 76 μm in human tissue and is responsible for its cytotoxic effects.
Actinium chemistry is almost entirely trivalent, with Ac³⁺ forming colorless or pale salts in the absence of colored counterions. Representative compounds include actinium oxide, Ac₂O₃, actinium fluoride, AcF₃, actinium chloride, AcCl₃, and actinium hydroxide, Ac(OH)₃. The ion is large and hard, so it favors oxygen- and fluorine-donor ligands and forms sparingly soluble fluorides, phosphates, oxalates, and hydroxides. Higher oxidation states are not established for ordinary actinium chemistry.
See more information at the Actinium compound page.
All actinium isotopes are radioactive, and safety depends strongly on isotope, activity, chemical form, and route of exposure. ²²⁷Ac is long-lived enough to persist and produces a chain of radioactive daughters, while ²²⁵Ac is a potent alpha emitter used only under controlled radiochemical conditions. Internal uptake is the principal concern because alpha particles cause severe local ionization in tissue. External gamma radiation from daughter products can also require shielding and remote handling.
Natural actinium occurs at trace levels in uranium-bearing minerals as part of decay chains and is continuously formed and lost by radioactive decay. In the environment Ac³⁺ is expected to bind strongly to mineral surfaces, organic matter, and phosphate- or carbonate-containing solids, limiting mobility under many conditions. It has no known biological role. Releases outside specialized nuclear or radiochemical settings are uncommon, and environmental behavior is inferred largely from tracer studies and analog chemistry.
Actinium is not traded as a bulk commodity. Usable quantities are obtained by radiochemical separation from decay products or by accelerator and reactor routes, depending on the isotope required. ²²⁵Ac supply is especially constrained because it must be isolated from suitable parent nuclides or produced by irradiation, followed by difficult purification from chemically similar actinides and radioactive daughters. Costs and availability are therefore governed by nuclear infrastructure, isotope purity, licensing, and short logistical timelines rather than mining demand. Recycling is mainly recovery from radiochemical processing streams.
Extremely rare, found in all uranium ores. Usually obtained by treating radium with neutrons in a reactor.
Actinium has no stable isotopes, so any primordial actinium has long since decayed. In nature and in planetary materials it exists only as a transient member of heavy-element decay chains, especially those derived from uranium and thorium. The heavy nuclei that ultimately feed these chains were produced by neutron-capture processes in earlier stellar events, but actinium itself is not a significant cosmic reservoir.
- Actinium was discovered through its radioactivity before its chemistry could be studied in ordinary amounts.
- The name comes from the Greek word for a ray or beam.
- ²²⁷Ac is a decay product in the ²³⁵U series.
- The element is usually handled at tracer scale, where carrier chemistry is often needed.
- Ac³⁺ is among the largest tripositive actinide ions.
- Separating actinium from lanthanum is chemically difficult because their ionic behavior is similar.
画像
性質
物理的性質
- 原子半径（経験値）
- 195 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
- 260 pm 全元素のファンデルワールス半径を比較 →
- 密度
- 1.007 × 104 kg/m³ 全元素の密度を比較 →
- モル体積
- 0.02254 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
- 1050.85 °C 全元素の融点を比較 →
- 沸点
- 3197.85 °C 全元素の沸点を比較 →
- 比熱容量
- 0.12 J/(g·K) 全元素の比熱容量を比較 →
- モル熱容量
- 27.2 J/(mol·K) 全元素のモル熱容量を比較 →
- 結晶構造
- 面心立方構造 全元素の結晶構造を比較 →
化学的性質
- 電気陰性度（Pauling）
- 1.1 全元素の電気陰性度（Pauling）を比較 →
- 電子親和力
- 0.35 eV
- 第1イオン化エネルギー
- 5.380235 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
- 11.75004 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
- 17.43606 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
- 44.800154 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
- 55.000189 eV 全元素の第5イオン化エネルギーを比較 →
- 酸化数
- +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
- [Rn] 7s2 6d1
熱力学的性質
- 融解熱
- 0.14510027 eV 全元素の融解熱を比較 →
- 蒸発熱
- 4.145722 eV 全元素の蒸発熱を比較 →
- 昇華熱
- 4.456651 eV
- 原子化熱
- 4.456651 eV
- 原子化エンタルピー
- 4.207908 eV
原子核
- 陽子数
- 89 全元素の陽子数を比較 →
- 中性子数
- 138 全元素の中性子数を比較 →
- 既知の同位体
- 33 全元素の既知の同位体を比較 →
- 安定同位体
- 0 全元素の安定同位体を比較 →
- 質量数（最も安定な同位体）
- 227
- 最も安定な同位体
- Ac-227
- 発見年
- 1899
存在度
- 存在度（地殻）
- 5.5e-10 mg/kg 全元素の存在度（地殻）を比較 →
結晶構造
- 格子定数a
- 531 pm
電子構造
- 各電子殻の電子数
- 2, 8, 18, 32, 18, 9, 2 全元素の各電子殻の電子数を比較 →
識別子
- CAS登録番号
- 7440-34-8 全元素のCAS登録番号を比較 →
- 項記号
- 2D3/2
- InChI
- InChI=1S/Ac
- InChI Key
- QQINRWTZWGJFDB-UHFFFAOYSA-N
電子配置 測定値
Ac: 6d¹ 7s²[Rn] 6d¹ 7s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 6d¹ 7s²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
安定同位体はありません。
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 |
|---|---|---|---|
| 212 放射性 | 212.007813 ± 0.000055 | データなし | 895 ms |
| 213 放射性 | 213.006609 ± 0.000056 | データなし | 738 ms |
| 216 放射性 | 216.008743 ± 0.000012 | データなし | 440 us |
| 210 放射性 | 210.009436 ± 0.000062 | データなし | 350 ms |
| 211 放射性 | 211.007732 ± 0.000057 | データなし | 213 ms |
相／状態
理由: 融点（1050.85 °C）より1025.8 °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89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 |
|---|---|---|---|---|
| Ac I | 0 | 153 | 95 | 113 |
| Ac II | +1 | 345 | 294 | 319 |
| Ac III | +2 | 11 | 11 | 11 |
| Ac IV | +3 | 6 | 0 | 0 |
準位データの収録状況 ?
| イオン | 電荷 | 準位 |
|---|---|---|
| Ac I | 0 | 53 |
| Ac II | +1 | 84 |
| Ac III | +2 | 8 |
| Ac IV | +3 | 2 |
| Ac V | +4 | 2 |
| Ac VI | +5 | 2 |
| Ac VII | +6 | 2 |
| Ac VIII | +7 | 2 |
| Ac IX | +8 | 2 |
| Ac X | +9 | 2 |
イオン半径
| 電荷 | 配位 | スピン | 半径 |
|---|---|---|---|
| +3 | 6 | データなし | 112.00000000000001 pm |
| +3 | 9 | データなし | 122 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 | |
|---|---|---|---|---|---|
| 212 放射性 | 212.007813 ± 0.000055 | データなし | 895 ms | α ≈100%β+ ? | |
| 213 放射性 | 213.006609 ± 0.000056 | データなし | 738 ms | α ≈100%β+ ? | |
| 216 放射性 | 216.008743 ± 0.000012 | データなし | 440 us | α =100%β+ ? | |
| 210 放射性 | 210.009436 ± 0.000062 | データなし | 350 ms | α ≈100%β+ ? | |
| 211 放射性 | 211.007732 ± 0.000057 | データなし | 213 ms | α ≈100%β+ ? |
スペクトル線
全213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 | |
|---|---|---|---|---|---|---|---|
| 391.4468 nm | 24000 | Ac II | emission | 6d.7s 3D → 5f.7s 3F* | 測定値 | NIST | |
| 417.99772 nm | 17000 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2D* | 測定値 | NIST | |
| 481.2218 nm | 16000 | Ac II | emission | 6d.7s 3D → 7s.7p 3P* | 測定値 | NIST | |
| 438.64 nm | 15000 | Ac II | emission | 6d.7s 1D → 6d.7p 1D* | 測定値 | NIST | |
| 397.736 nm | 13000 | Ac II | emission | 6d2 3F → 6d.7p 3P* | 測定値 | NIST | |
| 445.2188 nm | 12000 | Ac II | emission | 6d.7s 3D → 6d.7p 3F* | 測定値 | NIST | |
| 388.55592 nm | 9000 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2P* | 測定値 | NIST | |
| 401.9622 nm | 8700 | Ac II | emission | 6d2 3F → 5f.6d 1G* | 測定値 | NIST | |
| 544.6367 nm | 8700 | Ac II | emission | 6d2 3F → 6d.7p 3D* | 測定値 | NIST | |
| 435.9118 nm | 7300 | Ac II | emission | 6d.7s 3D → 7s.7p 3P* | 測定値 | NIST | |
| 446.27307 nm | 6900 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2F* | 測定値 | NIST | |
| 471.65807 nm | 6900 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2F* | 測定値 | NIST | |
| 495.8233 nm | 6800 | Ac II | emission | 6d.7s 1D → 6d.7p 1P* | 測定値 | NIST | |
| 384.304 nm | 6600 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2P* | 測定値 | NIST | |
| 392.0101 nm | 6500 | Ac II | emission | 6d2 3P → 5f.6d 1D* | 測定値 | NIST | |
| 418.31199 nm | 6400 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2F* | 測定値 | NIST | |
| 439.67158 nm | 5800 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2F* | 測定値 | NIST | |
| 419.43971 nm | 5300 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2P* | 測定値 | NIST | |
| 494.5181 nm | 5300 | Ac II | emission | 6d2 3F → 6d.7p 3D* | 測定値 | NIST | |
| 496.0869 nm | 4900 | Ac II | emission | 6d2 3F → 6d.7p 3D* | 測定値 | NIST | |
| 461.39285 nm | 4000 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2F* | 測定値 | NIST | |
| 527.15603 nm | 3800 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2F* | 測定値 | NIST | |
| 406.31064 nm | 3700 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2D* | 測定値 | NIST | |
| 407.8693 nm | 3700 | Ac II | emission | 6d.7s 3D → 6d.7p 1P* | 測定値 | NIST | |
| 403.4629 nm | 3500 | Ac I | emission | 6d.7s2 2D → 6d2.(3F).7p 4G* | 測定値 | NIST | |
| 420.9682 nm | 3500 | Ac II | emission | 6d.7s 3D → 5f.7s 1F* | 測定値 | NIST | |
| 669.5231 nm | 3300 | Ac II | emission | 6d2 3F → 6d.7p 3F* | 測定値 | NIST | |
| 474.0522 nm | 2600 | Ac II | emission | 6d2 1G → 6d.7p 1F* | 測定値 | NIST | |
| 515.6541 nm | 2100 | Ac II | emission | 6d2 3F → 5f.7s 3F* | 測定値 | NIST | |
| 383.53206 nm | 1900 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2P* | 測定値 | NIST | |
| 488.9102 nm | 1800 | Ac II | emission | 6d2 3F → 5f.7s 3F* | 測定値 | NIST | |
| 480.7843 nm | 1700 | Ac II | emission | 6d.7s 1D → 6d.7p 3F* | 測定値 | NIST | |
| 534.47384 nm | 1700 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4G* | 測定値 | NIST | |
| 400.5469 nm | 1500 | Ac II | emission | 6d2 1G → 5f.6d 3G* | 測定値 | NIST | |
| 536.2615 nm | 1400 | Ac II | emission | 6d2 3F → 6d.7p 1D* | 測定値 | NIST | |
| 522.8309 nm | 1300 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 4D* | 測定値 | NIST | |
| 454.408 nm | 1200 | Ac II | emission | 6d2 1D → 7s.7p 1P* | 測定値 | NIST | |
| 461.01055 nm | 1100 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2D* | 測定値 | NIST | |
| 422.599 nm | 1000 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4D* | 測定値 | NIST | |
| 387.7035 nm | 980 | Ac II | emission | 6d.7p 3P* → 5f.7p 3D | 測定値 | NIST | |
| 420.89072 nm | 960 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4D* | 測定値 | NIST | |
| 469.05284 nm | 960 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | 測定値 | NIST | |
| 521.5399 nm | 960 | Ac II | emission | 6d2 3P → 6d.7p 3P* | 測定値 | NIST | |
| 486.88523 nm | 890 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | 測定値 | NIST | |
| 526.4481 nm | 890 | Ac I | emission | 7s2.7p 2P* → 7s2.8s 2S | 測定値 | NIST | |
| 440.21056 nm | 860 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | 測定値 | NIST | |
| 447.18106 nm | 850 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | 測定値 | NIST | |
| 421.80204 nm | 740 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3P).7p 2D* | 測定値 | NIST | |
| 462.16811 nm | 710 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | 測定値 | NIST | |
| 426.8209 nm | 570 | Ac II | emission | 6d2 3F → 6d.7p 3P* | 測定値 | NIST |
詳細な性質
共有結合半径（詳細）
- 共有結合半径（Pyykkö）
- 186 pm
- 共有結合半径（Pyykkö、二重結合）
- 153 pm
- 共有結合半径（Pyykkö、三重結合）
- 140 pm
ファンデルワールス半径
- Alvarez
- 280 pm
- UFF
- 347.8 pm
- MM3
- 308 pm
原子半径と金属半径
- 原子半径（Rahm）
- 293 pm
番号付けの尺度
- Mendeleev
- 14
- Pettifor
- 48
- Glawe
- 33
電気陰性度の尺度
- Ghosh
- 0
分極率と分散
- 双極子分極率
- 203 a.u.
- 双極子分極率（不確かさ）
- 12 a.u.
相転移と同素体
| 融点 | 1323.15 K |
| 沸点 | 3473.15 K |
酸化数の分類
専門参考データ
結晶半径の詳細 (2)
| 電荷 | CN | スピン | rcrystal (pm) | 由来 |
|---|---|---|---|---|
| 3 | VI | 126 | from r^3 vs V plots, | |
| 3 | IX | — | 136 |
同位体の崩壊形式 (56)
| 同位体 | モード | 強度 |
|---|---|---|
| 205 | A | 100% |
| 205 | B+ | — |
| 206 | A | 100% |
| 206 | B+ | — |
| 207 | A | 100% |
| 208 | A | 100% |
| 208 | B+ | — |
| 209 | A | 100% |
| 209 | B+ | — |
| 210 | A | 100% |
X線散乱因子 (516)
| エネルギー (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1.19484 |
| 10.1617 | — | 1.15672 |
| 10.3261 | — | 1.11982 |
| 10.4931 | — | 1.0841 |
| 10.6628 | — | 1.04952 |
| 10.8353 | — | 1.01604 |
| 11.0106 | — | 0.98234 |
| 11.1886 | — | 0.94669 |
| 11.3696 | — | 0.91233 |
| 11.5535 | — | 0.88152 |
追加データ
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
5.5×10-10 milligrams per kilogram
参考文献 (1)
- [5] Actinium https://education.jlab.org/itselemental/ele089.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
参考文献 (1)
- [5] Actinium https://education.jlab.org/itselemental/ele089.html
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 Actinium.
The element property data was retrieved from publications.