Francium (Fr)
alkali-metalSolid
Standardatomgewicht
[223]Elektronenkonfiguration
[Rn] 7s1Schmelzpunkt
26,85 °CSiedepunkt
N/ADichte
1870 kg/m³Oxidationszustände
+1Elektronegativität (Pauling)
0,7Ionisierungsenergie (1.)
4,072741 eVEntdeckungsjahr
1939Atomradius
N/ADetails
Francium is the heaviest known alkali metal and a member of group 1. All of its isotopes are radioactive, and the element occurs naturally only as fleeting decay products in uranium and thorium series minerals. Its chemistry is expected and partly observed to resemble an extremely electropositive form of caesium, dominated by the +1 oxidation state. Because the longest-lived isotope, ²²³Fr, has a half-life of only about 22 minutes, francium has no bulk technological role.
Francium was discovered in 1939 by Marguerite Perey, a physicist at the Curie Institute in Paris, France (Fig. IUPAC.87.1). 223Fr (with a half-life of 22 min) occurs naturally in uranium minerals as a result of actinium decay. However, it is estimated that no more than approximately 30 g of francium is present in the Earth’s crust at any time. Francium can be produced artificially for research by bombarding thorium with protons. Francium was named in honor of Perey’s home country, France [575], [576], [577]. Francium has no known isotopic applications outside of scientific research.
Francium was discovered by Marguerite Catherine Perey, a French chemist, in 1939 while analyzing actinium's decay sequence. Although considered a natural element, scientists estimate that there is no more than one ounce of francium in the earth's crust at one time. Since there is so little naturally occurring francium on earth, scientists must produce francium in order to study it. Francium can be produced by bombarding thorium with protons or by bombarding radium with neutrons. Francium's most stable isotope, francium-223, has a half-life of about 22 minutes. It decays into radium-223 through beta decay or into astatine-219 through alpha decay.
Discovered in 1939 by Mlle. Marguerite Perey of the Curie Institute, Paris. Francium, the heaviest known member of the alkali metals series, occurs as a result of an alpha disintegration of actinium. It can also be made artificially by bombarding thorium with protons. While it occurs naturally in uranium minerals, there is probably less than an ounce of francium at any time in the total crust of the earth. It has the highest equivalent weight of any element, and is the most unstable of the first 101 elements of the periodic system. Thirty-three isotopes of francium are recognized. The longest lived 223Fr (Ac, K), a daughter of 227Ac, has a half-life of 22 min. This is the only isotope of francium occurring in nature. Because all known isotopes of francium are highly unstable, knowledge of the chemical properties of this element comes from radiochemical techniques. No weighable quantity of the element has been prepared or isolated. The chemical properties of francium most resemble cesium.
No macroscopic sample of pure francium has been prepared, so its actual bulk appearance is unknown. By periodic trend it is predicted to be a very soft, silvery metallic solid, but this has not been directly observed.
Francium has no commercial or industrial use. Its practical use is confined to research with very small numbers of atoms, especially laser spectroscopy, tests of atomic structure theory in very heavy alkali atoms, and studies relevant to fundamental symmetry measurements. ²²³Fr and other isotopes can be generated from nuclear decay or accelerator reactions, but their short half-lives restrict experiments to specialized laboratories and prevent storage or shipment as ordinary material.
Due to the small amounts produced and its short half-life, there are currently no uses for francium outside of basic scientific research.
Francium chemistry is difficult to study because only tracer quantities exist at any time. The stable oxidation state is Fr⁺, and no well-characterized bulk compounds are known. Experiments and periodic trends indicate close analogy with caesium salts, including expected ionic compounds such as francium chloride, FrCl, and francium hydroxide, FrOH. Complexation and adsorption studies show behavior consistent with a large, weakly hydrated alkali-metal cation, but many thermodynamic values remain estimated or derived from trace-scale measurements.
See more information at the Francium compound page.
Francium is hazardous primarily because all isotopes are radioactive and decay rapidly, emitting radiation through isotope-specific decay chains. The element is not encountered outside nuclear or radiochemical settings. Chemical toxicity is poorly characterized and is of little practical importance compared with radiological dose, contamination control, and the hazards associated with its radioactive daughters.
Natural francium is continually produced in minute amounts by decay within uranium- and thorium-bearing materials and then quickly decays, so it does not accumulate as a persistent environmental contaminant. Its environmental chemistry is inferred to follow alkali-metal ion behavior in water and minerals, but the number of atoms present in nature is so small that it has no known biological or geochemical cycling role.
Francium has no commodity market, no commercial supply chain, and no demand outside research. It cannot be mined in meaningful quantity because natural inventories are extraordinarily small and transient. Research samples are made as needed, commonly by separating ²²³Fr from actinium decay sources or by producing neutron-deficient isotopes in accelerator experiments. The limiting factors are specialized facilities, radiochemical handling, rapid decay, and the need to conduct measurements immediately after production.
Formed by decay of actinium. Chemical properties similar to cesium. Decays to radium or astatine.
Francium is not a significant cosmic element. Any primordial francium would have decayed long ago, and present atoms arise only from ongoing radioactive decay or nuclear reactions. In stars, supernova debris, and planetary materials it is expected to be transient and extremely rare, with no stable isotope allowing accumulation over geological or astronomical time.
- Francium was discovered through its decay signature rather than from an isolated visible sample.
- Only trace radiochemical amounts can exist before most atoms decay away.
- ²²³Fr belongs to the actinium decay series.
- Francium is less well characterized experimentally than many synthetic elements with longer-lived isotopes.
- Its first ionization energy is among the lowest expected for any known element.
Bilder
Eigenschaften
Physikalisch
- Kovalenzradius
- 260 pm Vergleiche Kovalenzradius aller Elemente →
- Van-der-Waals-Radius
- 348 pm Vergleiche Van-der-Waals-Radius aller Elemente →
- Dichte
- 1870 kg/m³ Vergleiche Dichte aller Elemente →
- Aggregatzustand bei Standardbedingungen
- Fest Vergleiche Aggregatzustand bei Standardbedingungen aller Elemente →
- Schmelzpunkt
- 26,85 °C Vergleiche Schmelzpunkt aller Elemente →
- Kristallstruktur
- Raumzentriert kubisch Vergleiche Kristallstruktur aller Elemente →
Chemisch
- Elektronegativität (Pauling)
- 0,7 Vergleiche Elektronegativität (Pauling) aller Elemente →
- Elektronegativität (Allen)
- 0,67
- Elektronenaffinität
- 0,491 eV
- Ionisierungsenergie (1.)
- 4,072741 eV Vergleiche Ionisierungsenergie (1.) aller Elemente →
- Ionisierungsenergie (2.)
- 22,400077 eV Vergleiche Ionisierungsenergie (2.) aller Elemente →
- Ionisierungsenergie (3.)
- 33,500115 eV Vergleiche Ionisierungsenergie (3.) aller Elemente →
- Ionisierungsenergie (4.)
- 39,100135 eV Vergleiche Ionisierungsenergie (4.) aller Elemente →
- Ionisierungsenergie (5.)
- 50,000172 eV Vergleiche Ionisierungsenergie (5.) aller Elemente →
- Oxidationszustände
- +1 Vergleiche Oxidationszustände aller Elemente →
- Valenzelektronen
- 1 Vergleiche Valenzelektronen aller Elemente →
- Elektronenkonfiguration
- [Rn] 7s1
Thermodynamisch
- Schmelzwärme
- 0,02072861 eV Vergleiche Schmelzwärme aller Elemente →
- Verdampfungswärme
- 0,67367985 eV Vergleiche Verdampfungswärme aller Elemente →
- Sublimationswärme
- 0,74622998 eV
- Atomisierungswärme
- 0,74622998 eV
Nuklear
- Protonen
- 87 Vergleiche Protonen aller Elemente →
- Neutronen
- 136 Vergleiche Neutronen aller Elemente →
- Bekannte Isotope
- 37 Vergleiche Bekannte Isotope aller Elemente →
- Stabile Isotope
- 0 Vergleiche Stabile Isotope aller Elemente →
- Massenzahl (stabilstes)
- 223
- Stabilstes Isotop
- Fr-223
- Entdeckungsjahr
- 1939
Häufigkeit
N/A
Kristallstruktur
N/A
Elektronische Struktur
- Elektronen pro Schale
- 2, 8, 18, 32, 18, 8, 1 Vergleiche Elektronen pro Schale aller Elemente →
Identifikatoren
- CAS-Nummer
- 7440-73-5 Vergleiche CAS-Nummer aller Elemente →
- Termsymbol
- 2S1/2
- InChI
- InChI=1S/Fr
- InChI-Key
- KLMCZVJOEAUDNE-UHFFFAOYSA-N
Elektronenkonfiguration Gemessen
Fr: 7s¹[Rn] 7s¹1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 7s¹Atommodell
Isotope ändern die Neutronenzahl, Masse und Stabilität — nicht die Elektronenkonfiguration eines neutralen Atoms.
Schematisches Atommodell, nicht maßstabsgetreu.
Atomarer Fingerabdruck
Emissions- / Absorptionsspektrum
Isotopenverteilung
Keine stabilen Isotope.
| Massenzahl | Atommasse (u) | Natürliche Häufigkeit | Halbwertszeit |
|---|---|---|---|
| 233 Radioaktiv | 233,05264 ± 0,00032 | N/A | 900 ms |
| 216 Radioaktiv | 216,0031899 ± 0,0000045 | N/A | 700 ns |
| 203 Radioaktiv | 203,0009407 ± 0,0000067 | N/A | 550 ms |
| 202 Radioaktiv | 202,00332 ± 0,000055 | N/A | 372 ms |
| 215 Radioaktiv | 215,0003418 ± 0,0000076 | N/A | 90 ns |
Phase / Zustand
Grund: 1,9 °C unter Schmelzpunkt (26,85 °C)
Schematisch, nicht maßstabsgetreu
Phasenübergangspunkte
Übergangsenergien
Energie benötigt, um 1 mol am Schmelzpunkt zu schmelzen
Energie benötigt, um 1 mol am Siedepunkt zu verdampfen
Energie benötigt, um 1 mol am Sublimationspunkt zu sublimieren
Dichte
Bei Standardbedingungen
Bei Standardbedingungen
Atomspektren
10 von 87 angezeigt. Sortiert nach Ionenladung (aufsteigend).
Liniendaten ?
| Ion | Ladung | Gesamtlinien | Übergangswahrscheinlichkeiten | Niveau-Bezeichnungen |
|---|---|---|---|---|
| Fr I | 0 | 149 | 149 | 149 |
Niveaudaten ?
| Ion | Ladung | Niveaus |
|---|---|---|
| Fr I | 0 | 123 |
| Fr II | +1 | 2 |
| Fr III | +2 | 2 |
| Fr IV | +3 | 2 |
| Fr V | +4 | 2 |
| Fr VI | +5 | 2 |
| Fr VII | +6 | 2 |
| Fr VIII | +7 | 2 |
| Fr IX | +8 | 2 |
| Fr X | +9 | 2 |
Kristallstrukturdaten nicht verfügbar
Kristallstruktur: bcc
Ionenradien
| Ladung | Koordination | Spin | Radius |
|---|---|---|---|
| +1 | 6 | N/A | 180 pm |
Verbindungen
Isotope (5)
| Massenzahl | Atommasse (u) | Natürliche Häufigkeit | Halbwertszeit | Zerfallsart | |
|---|---|---|---|---|---|
| 233 Radioaktiv | 233,05264 ± 0,00032 | N/A | 900 ms | β- =100%β-n ? | |
| 216 Radioaktiv | 216,0031899 ± 0,0000045 | N/A | 700 ns | α =100%β+ ? | |
| 203 Radioaktiv | 203,0009407 ± 0,0000067 | N/A | 550 ms | α ≈100%β+ ? | |
| 202 Radioaktiv | 202,00332 ± 0,000055 | N/A | 372 ms | α ≈100%β+ ? | |
| 215 Radioaktiv | 215,0003418 ± 0,0000076 | N/A | 90 ns | α =100% |
Spektrallinien
| Wellenlänge (nm) | Intensität | Ionenstufe | Typ | Übergang | Genauigkeit | Quelle | |
|---|---|---|---|---|---|---|---|
| 422.56552 nm | N/A | Fr I | emission | 7s 2S → 8p 2P* | Gemessen | NIST | |
| 432.53607 nm | N/A | Fr I | emission | 7s 2S → 8p 2P* | Gemessen | NIST | |
| 494.61573 nm | N/A | Fr I | emission | 7p 2P* → 20d 2D | Gemessen | NIST | |
| 495.91444 nm | N/A | Fr I | emission | 7p 2P* → 19d 2D | Gemessen | NIST | |
| 496.90308 nm | N/A | Fr I | emission | 7p 2P* → 20s 2S | Gemessen | NIST | |
| 497.49878 nm | N/A | Fr I | emission | 7p 2P* → 18d 2D | Gemessen | NIST | |
| 498.7192 nm | N/A | Fr I | emission | 7p 2P* → 19s 2S | Gemessen | NIST | |
| 499.45999 nm | N/A | Fr I | emission | 7p 2P* → 17d 2D | Gemessen | NIST | |
| 500.99176 nm | N/A | Fr I | emission | 7p 2P* → 18s 2S | Gemessen | NIST | |
| 501.92929 nm | N/A | Fr I | emission | 7p 2P* → 16d 2D | Gemessen | NIST | |
| 503.88964 nm | N/A | Fr I | emission | 7p 2P* → 17s 2S | Gemessen | NIST | |
| 505.10105 nm | N/A | Fr I | emission | 7p 2P* → 15d 2D | Gemessen | NIST | |
| 507.66912 nm | N/A | Fr I | emission | 7p 2P* → 16s 2S | Gemessen | NIST | |
| 509.27532 nm | N/A | Fr I | emission | 7p 2P* → 14d 2D | Gemessen | NIST | |
| 512.73622 nm | N/A | Fr I | emission | 7p 2P* → 15s 2S | Gemessen | NIST | |
| 514.93307 nm | N/A | Fr I | emission | 7p 2P* → 13d 2D | Gemessen | NIST | |
| 519.7664 nm | N/A | Fr I | emission | 7p 2P* → 14s 2S | Gemessen | NIST | |
| 522.89168 nm | N/A | Fr I | emission | 7p 2P* → 12d 2D | Gemessen | NIST | |
| 529.95916 nm | N/A | Fr I | emission | 7p 2P* → 13s 2S | Gemessen | NIST | |
| 534.64166 nm | N/A | Fr I | emission | 7p 2P* → 11d 2D | Gemessen | NIST | |
| 539.61762 nm | N/A | Fr I | emission | 7p 2P* → 20d 2D | Gemessen | NIST | |
| 539.6469 nm | N/A | Fr I | emission | 7p 2P* → 20d 2D | Gemessen | NIST | |
| 541.15779 nm | N/A | Fr I | emission | 7p 2P* → 19d 2D | Gemessen | NIST | |
| 541.19321 nm | N/A | Fr I | emission | 7p 2P* → 19d 2D | Gemessen | NIST | |
| 542.37083 nm | N/A | Fr I | emission | 7p 2P* → 20s 2S | Gemessen | NIST | |
| 543.03716 nm | N/A | Fr I | emission | 7p 2P* → 18d 2D | Gemessen | NIST | |
| 543.08061 nm | N/A | Fr I | emission | 7p 2P* → 18d 2D | Gemessen | NIST | |
| 544.53524 nm | N/A | Fr I | emission | 7p 2P* → 19s 2S | Gemessen | NIST | |
| 545.36417 nm | N/A | Fr I | emission | 7p 2P* → 17d 2D | Gemessen | NIST | |
| 545.4185 nm | N/A | Fr I | emission | 7p 2P* → 17d 2D | Gemessen | NIST | |
| 545.63748 nm | N/A | Fr I | emission | 7p 2P* → 12s 2S | Gemessen | NIST | |
| 547.24565 nm | N/A | Fr I | emission | 7p 2P* → 18s 2S | Gemessen | NIST | |
| 548.29545 nm | N/A | Fr I | emission | 7p 2P* → 16d 2D | Gemessen | NIST | |
| 548.36447 nm | N/A | Fr I | emission | 7p 2P* → 16d 2D | Gemessen | NIST | |
| 550.70515 nm | N/A | Fr I | emission | 7p 2P* → 17s 2S | Gemessen | NIST | |
| 552.06365 nm | N/A | Fr I | emission | 7p 2P* → 15d 2D | Gemessen | NIST | |
| 552.15244 nm | N/A | Fr I | emission | 7p 2P* → 15d 2D | Gemessen | NIST | |
| 553.17161 nm | N/A | Fr I | emission | 7p 2P* → 10d 2D | Gemessen | NIST | |
| 555.22268 nm | N/A | Fr I | emission | 7p 2P* → 16s 2S | Gemessen | NIST | |
| 557.02549 nm | N/A | Fr I | emission | 7p 2P* → 14d 2D | Gemessen | NIST | |
| 557.14445 nm | N/A | Fr I | emission | 7p 2P* → 14d 2D | Gemessen | NIST | |
| 561.28917 nm | N/A | Fr I | emission | 7p 2P* → 15s 2S | Gemessen | NIST | |
| 563.7589 nm | N/A | Fr I | emission | 7p 2P* → 13d 2D | Gemessen | NIST | |
| 563.92284 nm | N/A | Fr I | emission | 7p 2P* → 13d 2D | Gemessen | NIST | |
| 569.72475 nm | N/A | Fr I | emission | 7p 2P* → 14s 2S | Gemessen | NIST | |
| 571.87464 nm | N/A | Fr I | emission | 7p 2P* → 11s 2S | Gemessen | NIST | |
| 573.24676 nm | N/A | Fr I | emission | 7p 2P* → 12d 2D | Gemessen | NIST | |
| 573.48185 nm | N/A | Fr I | emission | 7p 2P* → 12d 2D | Gemessen | NIST | |
| 585.3491 nm | N/A | Fr I | emission | 7p 2P* → 9d 2D | Gemessen | NIST | |
| 587.29 nm | N/A | Fr I | emission | 7p 2P* → 11d 2D | Gemessen | NIST | |
| 587.64619 nm | N/A | Fr I | emission | 7p 2P* → 11d 2D | Gemessen | NIST | |
| 600.95745 nm | N/A | Fr I | emission | 7p 2P* → 12s 2S | Gemessen | NIST | |
| 609.52762 nm | N/A | Fr I | emission | 7p 2P* → 10d 2D | Gemessen | NIST | |
| 610.10952 nm | N/A | Fr I | emission | 7p 2P* → 10d 2D | Gemessen | NIST | |
| 618.5596 nm | N/A | Fr I | emission | 6d 2D → 20p 2P* | Gemessen | NIST | |
| 618.7831 nm | N/A | Fr I | emission | 6d 2D → 20p 2P* | Gemessen | NIST | |
| 621.0658 nm | N/A | Fr I | emission | 6d 2D → 19p 2P* | Gemessen | NIST | |
| 621.3414 nm | N/A | Fr I | emission | 6d 2D → 19p 2P* | Gemessen | NIST | |
| 621.98126 nm | N/A | Fr I | emission | 7p 2P* → 10s 2S | Gemessen | NIST | |
| 624.178 nm | N/A | Fr I | emission | 6d 2D → 18p 2P* | Gemessen | NIST | |
| 624.5235 nm | N/A | Fr I | emission | 6d 2D → 18p 2P* | Gemessen | NIST | |
| 626.3009 nm | N/A | Fr I | emission | 6d 2D → 20p 2P* | Gemessen | NIST | |
| 628.1118 nm | N/A | Fr I | emission | 6d 2D → 17p 2P* | Gemessen | NIST | |
| 628.5529 nm | N/A | Fr I | emission | 6d 2D → 17p 2P* | Gemessen | NIST | |
| 628.8704 nm | N/A | Fr I | emission | 6d 2D → 19p 2P* | Gemessen | NIST | |
| 632.0616 nm | N/A | Fr I | emission | 6d 2D → 18p 2P* | Gemessen | NIST | |
| 632.9403 nm | N/A | Fr I | emission | 7p 2P* → 11s 2S | Gemessen | NIST | |
| 633.1901 nm | N/A | Fr I | emission | 6d 2D → 16p 2P* | Gemessen | NIST | |
| 633.7661 nm | N/A | Fr I | emission | 6d 2D → 16p 2P* | Gemessen | NIST | |
| 636.0957 nm | N/A | Fr I | emission | 6d 2D → 17p 2P* | Gemessen | NIST | |
| 639.9141 nm | N/A | Fr I | emission | 6d 2D → 15p 2P* | Gemessen | NIST | |
| 640.6887 nm | N/A | Fr I | emission | 6d 2D → 15p 2P* | Gemessen | NIST | |
| 641.3044 nm | N/A | Fr I | emission | 6d 2D → 16p 2P* | Gemessen | NIST | |
| 648.2027 nm | N/A | Fr I | emission | 6d 2D → 15p 2P* | Gemessen | NIST | |
| 648.421 nm | N/A | Fr I | emission | 7p 2P* → 9d 2D | Gemessen | NIST | |
| 649.103 nm | N/A | Fr I | emission | 6d 2D → 14p 2P* | Gemessen | NIST | |
| 649.4876 nm | N/A | Fr I | emission | 7p 2P* → 9d 2D | Gemessen | NIST | |
| 650.1812 nm | N/A | Fr I | emission | 6d 2D → 14p 2P* | Gemessen | NIST | |
| 650.7242 nm | N/A | Fr I | emission | 7p 2P* → 8d 2D | Gemessen | NIST | |
| 657.633 nm | N/A | Fr I | emission | 6d 2D → 14p 2P* | Gemessen | NIST | |
| 662.174 nm | N/A | Fr I | emission | 6d 2D → 13p 2P* | Gemessen | NIST | |
| 663.746 nm | N/A | Fr I | emission | 6d 2D → 13p 2P* | Gemessen | NIST | |
| 671.054 nm | N/A | Fr I | emission | 6d 2D → 13p 2P* | Gemessen | NIST | |
| 681.787 nm | N/A | Fr I | emission | 6d 2D → 12p 2P* | Gemessen | NIST | |
| 684.222 nm | N/A | Fr I | emission | 6d 2D → 12p 2P* | Gemessen | NIST | |
| 691.204 nm | N/A | Fr I | emission | 6d 2D → 12p 2P* | Gemessen | NIST | |
| 694.8987 nm | N/A | Fr I | emission | 7p 2P* → 10s 2S | Gemessen | NIST | |
| 713.491 nm | N/A | Fr I | emission | 6d 2D → 11p 2P* | Gemessen | NIST | |
| 717.615 nm | N/A | Fr I | emission | 6d 2D → 11p 2P* | Gemessen | NIST | |
| 717.98664 nm | N/A | Fr I | emission | 7s 2S → 7p 2P* | Gemessen | NIST | |
| 723.811 nm | N/A | Fr I | emission | 6d 2D → 11p 2P* | Gemessen | NIST | |
| 728.5892 nm | N/A | Fr I | emission | 7p 2P* → 8d 2D | Gemessen | NIST | |
| 730.9713 nm | N/A | Fr I | emission | 7p 2P* → 8d 2D | Gemessen | NIST | |
| 744.1976 nm | N/A | Fr I | emission | 7p 2P* → 9s 2S | Gemessen | NIST |
Erweiterte Eigenschaften
Kovalente Radien (Erweitert)
- Kovalenzradius (Pyykkö)
- 223 pm
- Kovalenzradius (Pyykkö, doppelt)
- 218 pm
Van-der-Waals-Radien
- Truhlar
- 348 pm
- UFF
- 490 pm
- MM3
- 364 pm
Atom- & Metallische Radien
- Atomradius (Rahm)
- 258 pm
Nummerierungsskalen
- Mendeleev
- 6
- Pettifor
- 7
- Glawe
- 7
Elektronegativitätsskalen
- Ghosh
- 0
Polarisierbarkeit & Dispersion
- Dipolpolarisierbarkeit
- 317,8 a.u.
- Dipolpolarisierbarkeit (Uns.)
- 2,4 a.u.
Phasenübergänge & Allotrope
| Schmelzpunkt | 294,15 K |
Oxidationszustands-Kategorien
Erweiterte Referenzdaten
Kristallradien-Details (1)
| Ladung | CN | Spin | rcrystal (pm) | Herkunft |
|---|---|---|---|---|
| 1 | VI | 194 | Ahrens (1952) ionic radius, |
Isotopenzerfallsarten (60)
| Isotop | Modus | Intensität |
|---|---|---|
| 197 | A | 100% |
| 198 | A | 100% |
| 199 | A | 100% |
| 199 | B+ | — |
| 200 | A | 100% |
| 200 | B+ | — |
| 200 | B+SF | — |
| 201 | A | 100% |
| 201 | B+ | — |
| 202 | A | 100% |
Röntgenstreufaktoren (516)
| Energie (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 0,05044 |
| 10,1617 | — | 0,06059 |
| 10,3261 | — | 0,07277 |
| 10,4931 | — | 0,08938 |
| 10,6628 | — | 0,11712 |
| 10,8353 | — | 0,15347 |
| 11,0106 | — | 0,20109 |
| 11,1886 | — | 0,26349 |
| 11,3696 | — | 0,40321 |
| 11,5535 | — | 0,63759 |
Zusätzliche Daten
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
Referenzen (1)
- [5] Francium https://education.jlab.org/itselemental/ele087.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
Referenzen (1)
- [5] Francium https://education.jlab.org/itselemental/ele087.html
Referenzen
(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 Francium.
The element property data was retrieved from publications.