Actinium (Ac)
actinideSolid
Peso atômico padrão
[227]Configuração eletrônica
[Rn] 7s2 6d1Ponto de fusão
1050,85 °CPonto de ebulição
3197,85 °CDensidade
1,007e+4 kg/m³Estados de oxidação
+3Eletronegatividade (Pauling)
1,1Energia de ionização (1ª)
5,380235 eVAno da descoberta
1899Raio atômico
195 pmDetalhes
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.
Imagens
Propriedades
Física
- Raio atômico (empírico)
- 195 pm Comparar Raio atômico (empírico) de todos os elementos →
- Raio covalente
- 215 pm Comparar Raio covalente de todos os elementos →
- Raio de van der Waals
- 260 pm Comparar Raio de van der Waals de todos os elementos →
- Densidade
- 1,007 × 104 kg/m³ Comparar Densidade de todos os elementos →
- Volume molar
- 0,02254 L/mol
- Fase nas CNTP
- Sólido Comparar Fase nas CNTP de todos os elementos →
- Ponto de fusão
- 1050,85 °C Comparar Ponto de fusão de todos os elementos →
- Ponto de ebulição
- 3197,85 °C Comparar Ponto de ebulição de todos os elementos →
- Capacidade calorífica específica
- 0,12 J/(g·K) Comparar Capacidade calorífica específica de todos os elementos →
- Capacidade calorífica molar
- 27,2 J/(mol·K) Comparar Capacidade calorífica molar de todos os elementos →
- Estrutura cristalina
- Cúbica de faces centradas Comparar Estrutura cristalina de todos os elementos →
Química
- Eletronegatividade (Pauling)
- 1,1 Comparar Eletronegatividade (Pauling) de todos os elementos →
- Afinidade eletrônica
- 0,35 eV
- Energia de ionização (1ª)
- 5,380235 eV Comparar Energia de ionização (1ª) de todos os elementos →
- Energia de ionização (2ª)
- 11,75004 eV Comparar Energia de ionização (2ª) de todos os elementos →
- Energia de ionização (3ª)
- 17,43606 eV Comparar Energia de ionização (3ª) de todos os elementos →
- Energia de ionização (4ª)
- 44,800154 eV Comparar Energia de ionização (4ª) de todos os elementos →
- Energia de ionização (5ª)
- 55,000189 eV Comparar Energia de ionização (5ª) de todos os elementos →
- Estados de oxidação
- +3 Comparar Estados de oxidação de todos os elementos →
- Elétrons de valência
- 3 Comparar Elétrons de valência de todos os elementos →
- Configuração eletrônica
- [Rn] 7s2 6d1
Termodinâmica
- Calor de fusão
- 0,14510027 eV Comparar Calor de fusão de todos os elementos →
- Calor de vaporização
- 4,145722 eV Comparar Calor de vaporização de todos os elementos →
- Calor de sublimação
- 4,456651 eV
- Calor de atomização
- 4,456651 eV
- Entalpia de atomização
- 4,207908 eV
Nuclear
- Prótons
- 89 Comparar Prótons de todos os elementos →
- Nêutrons
- 138 Comparar Nêutrons de todos os elementos →
- Isótopos conhecidos
- 33 Comparar Isótopos conhecidos de todos os elementos →
- Isótopos estáveis
- 0 Comparar Isótopos estáveis de todos os elementos →
- Número de massa (mais estável)
- 227
- Isótopo mais estável
- Ac-227
- Ano da descoberta
- 1899
Abundância
- Abundância (crosta terrestre)
- 5,5e-10 mg/kg Comparar Abundância (crosta terrestre) de todos os elementos →
Estrutura cristalina
- Constante de rede a
- 531 pm
Estrutura eletrônica
- Elétrons por camada
- 2, 8, 18, 32, 18, 9, 2 Comparar Elétrons por camada de todos os elementos →
Identificadores
- Número CAS
- 7440-34-8 Comparar Número CAS de todos os elementos →
- Símbolo de termo
- 2D3/2
- InChI
- InChI=1S/Ac
- Chave InChI
- QQINRWTZWGJFDB-UHFFFAOYSA-N
Configuração eletrônica Medido
Ac: 6d¹ 7s²[Rn] 6d¹ 7s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 6d¹ 7s²Modelo atômico
Os isótopos alteram o número de nêutrons, a massa e a estabilidade — não a configuração eletrônica de um átomo neutro.
Modelo atômico esquemático, sem escala.
Assinatura atômica
Espectro de emissão / absorção
Distribuição isotópica
Sem isótopos estáveis.
| Número de massa | Massa atômica (u) | Abundância natural | Meia-vida |
|---|---|---|---|
| 212 Radioativo | 212,007813 ± 0,000055 | N/D | 895 ms |
| 213 Radioativo | 213,006609 ± 0,000056 | N/D | 738 ms |
| 216 Radioativo | 216,008743 ± 0,000012 | N/D | 440 us |
| 210 Radioativo | 210,009436 ± 0,000062 | N/D | 350 ms |
| 211 Radioativo | 211,007732 ± 0,000057 | N/D | 213 ms |
Fase / Estado
Motivo: 1025,8 °C abaixo do ponto de fusão (1050,85 °C)
Esquemático, sem escala
Pontos de transição de fase
Energias de transição
Energia necessária para fundir 1 mol no ponto de fusão
Energia necessária para vaporizar 1 mol no ponto de ebulição
Energia necessária para sublimar 1 mol no ponto de sublimação
Densidade
Em condições padrão
Em condições padrão
Espectros atômicos
Mostrando 10 de 89. Ordenado por carga do íon (ordem crescente).
Dados de linhas disponíveis ?
| Íon | Carga | Total de linhas | Probabilidades de transição | Designações dos níveis |
|---|---|---|---|---|
| Ac I | 0 | 153 | 95 | 113 |
| Ac II | +1 | 345 | 294 | 319 |
| Ac III | +2 | 11 | 11 | 11 |
| Ac IV | +3 | 6 | 0 | 0 |
Dados de níveis disponíveis ?
| Íon | Carga | Níveis |
|---|---|---|
| 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 |
Raios iônicos
| Carga | Coordenação | Spin | Raio |
|---|---|---|---|
| +3 | 6 | N/D | 112.00000000000001 pm |
| +3 | 9 | N/D | 122 pm |
Compostos
Isótopos (5)
| Número de massa | Massa atômica (u) | Abundância natural | Meia-vida | Modo de decaimento | |
|---|---|---|---|---|---|
| 212 Radioativo | 212,007813 ± 0,000055 | N/D | 895 ms | α ≈100%β+ ? | |
| 213 Radioativo | 213,006609 ± 0,000056 | N/D | 738 ms | α ≈100%β+ ? | |
| 216 Radioativo | 216,008743 ± 0,000012 | N/D | 440 us | α =100%β+ ? | |
| 210 Radioativo | 210,009436 ± 0,000062 | N/D | 350 ms | α ≈100%β+ ? | |
| 211 Radioativo | 211,007732 ± 0,000057 | N/D | 213 ms | α ≈100%β+ ? |
Linhas espectrais
Mostrando 50 de 213. Por padrão, são mostradas apenas as linhas espectrais com intensidade medida.
| Comprimento de onda (nm) | Intensidade | Estágio de ionização | Tipo | Transição | Exatidão | Fonte | |
|---|---|---|---|---|---|---|---|
| 391.4468 nm | 24000 | Ac II | emission | 6d.7s 3D → 5f.7s 3F* | Medida | NIST | |
| 417.99772 nm | 17000 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2D* | Medida | NIST | |
| 481.2218 nm | 16000 | Ac II | emission | 6d.7s 3D → 7s.7p 3P* | Medida | NIST | |
| 438.64 nm | 15000 | Ac II | emission | 6d.7s 1D → 6d.7p 1D* | Medida | NIST | |
| 397.736 nm | 13000 | Ac II | emission | 6d2 3F → 6d.7p 3P* | Medida | NIST | |
| 445.2188 nm | 12000 | Ac II | emission | 6d.7s 3D → 6d.7p 3F* | Medida | NIST | |
| 388.55592 nm | 9000 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2P* | Medida | NIST | |
| 401.9622 nm | 8700 | Ac II | emission | 6d2 3F → 5f.6d 1G* | Medida | NIST | |
| 544.6367 nm | 8700 | Ac II | emission | 6d2 3F → 6d.7p 3D* | Medida | NIST | |
| 435.9118 nm | 7300 | Ac II | emission | 6d.7s 3D → 7s.7p 3P* | Medida | NIST | |
| 446.27307 nm | 6900 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2F* | Medida | NIST | |
| 471.65807 nm | 6900 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2F* | Medida | NIST | |
| 495.8233 nm | 6800 | Ac II | emission | 6d.7s 1D → 6d.7p 1P* | Medida | NIST | |
| 384.304 nm | 6600 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2P* | Medida | NIST | |
| 392.0101 nm | 6500 | Ac II | emission | 6d2 3P → 5f.6d 1D* | Medida | NIST | |
| 418.31199 nm | 6400 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2F* | Medida | NIST | |
| 439.67158 nm | 5800 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2F* | Medida | NIST | |
| 419.43971 nm | 5300 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2P* | Medida | NIST | |
| 494.5181 nm | 5300 | Ac II | emission | 6d2 3F → 6d.7p 3D* | Medida | NIST | |
| 496.0869 nm | 4900 | Ac II | emission | 6d2 3F → 6d.7p 3D* | Medida | NIST | |
| 461.39285 nm | 4000 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 2F* | Medida | NIST | |
| 527.15603 nm | 3800 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2F* | Medida | NIST | |
| 406.31064 nm | 3700 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2D* | Medida | NIST | |
| 407.8693 nm | 3700 | Ac II | emission | 6d.7s 3D → 6d.7p 1P* | Medida | NIST | |
| 403.4629 nm | 3500 | Ac I | emission | 6d.7s2 2D → 6d2.(3F).7p 4G* | Medida | NIST | |
| 420.9682 nm | 3500 | Ac II | emission | 6d.7s 3D → 5f.7s 1F* | Medida | NIST | |
| 669.5231 nm | 3300 | Ac II | emission | 6d2 3F → 6d.7p 3F* | Medida | NIST | |
| 474.0522 nm | 2600 | Ac II | emission | 6d2 1G → 6d.7p 1F* | Medida | NIST | |
| 515.6541 nm | 2100 | Ac II | emission | 6d2 3F → 5f.7s 3F* | Medida | NIST | |
| 383.53206 nm | 1900 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2P* | Medida | NIST | |
| 488.9102 nm | 1800 | Ac II | emission | 6d2 3F → 5f.7s 3F* | Medida | NIST | |
| 480.7843 nm | 1700 | Ac II | emission | 6d.7s 1D → 6d.7p 3F* | Medida | NIST | |
| 534.47384 nm | 1700 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4G* | Medida | NIST | |
| 400.5469 nm | 1500 | Ac II | emission | 6d2 1G → 5f.6d 3G* | Medida | NIST | |
| 536.2615 nm | 1400 | Ac II | emission | 6d2 3F → 6d.7p 1D* | Medida | NIST | |
| 522.8309 nm | 1300 | Ac I | emission | 6d.7s2 2D → 6d.7s.(3D).7p 4D* | Medida | NIST | |
| 454.408 nm | 1200 | Ac II | emission | 6d2 1D → 7s.7p 1P* | Medida | NIST | |
| 461.01055 nm | 1100 | Ac I | emission | 6d.7s2 2D → 6d.7s.(1D).7p 2D* | Medida | NIST | |
| 422.599 nm | 1000 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4D* | Medida | NIST | |
| 387.7035 nm | 980 | Ac II | emission | 6d.7p 3P* → 5f.7p 3D | Medida | NIST | |
| 420.89072 nm | 960 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4D* | Medida | NIST | |
| 469.05284 nm | 960 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | Medida | NIST | |
| 521.5399 nm | 960 | Ac II | emission | 6d2 3P → 6d.7p 3P* | Medida | NIST | |
| 486.88523 nm | 890 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | Medida | NIST | |
| 526.4481 nm | 890 | Ac I | emission | 7s2.7p 2P* → 7s2.8s 2S | Medida | NIST | |
| 440.21056 nm | 860 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | Medida | NIST | |
| 447.18106 nm | 850 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | Medida | NIST | |
| 421.80204 nm | 740 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3P).7p 2D* | Medida | NIST | |
| 462.16811 nm | 710 | Ac I | emission | 6d2.(3F).7s 4F → 6d2.(3F).7p 4F* | Medida | NIST | |
| 426.8209 nm | 570 | Ac II | emission | 6d2 3F → 6d.7p 3P* | Medida | NIST |
Propriedades ampliadas
Raios covalentes (dados ampliados)
- Raio covalente (Pyykkö)
- 186 pm
- Raio covalente (Pyykkö, ligação dupla)
- 153 pm
- Raio covalente (Pyykkö, ligação tripla)
- 140 pm
Raios de van der Waals
- Alvarez
- 280 pm
- UFF
- 347,8 pm
- MM3
- 308 pm
Raios atômicos e metálicos
- Raio atômico (Rahm)
- 293 pm
Escalas de numeração
- Mendeleev
- 14
- Pettifor
- 48
- Glawe
- 33
Escalas de eletronegatividade
- Ghosh
- 0
Polarizabilidade e dispersão
- Polarizabilidade dipolar
- 203 a.u.
- Polarizabilidade dipolar (incerteza)
- 12 a.u.
Transições de fase e alótropos
| Ponto de fusão | 1323,15 K |
| Ponto de ebulição | 3473,15 K |
Categorias de estados de oxidação
Dados de referência avançados
Detalhes dos raios cristalinos (2)
| Carga | CN | Spin | rcrystal (pm) | Origem |
|---|---|---|---|---|
| 3 | VI | 126 | from r^3 vs V plots, | |
| 3 | IX | — | 136 |
Modos de decaimento dos isótopos (56)
| Isótopo | Modo | Intensidade |
|---|---|---|
| 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% |
Fatores de espalhamento de raios X (516)
| Energia (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 |
Dados adicionais
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
5.5×10-10 milligrams per kilogram
Referências (1)
- [5] Actinium https://education.jlab.org/itselemental/ele089.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
Referências (1)
- [5] Actinium https://education.jlab.org/itselemental/ele089.html
Referências
(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.