Hassium (Hs)
transition-metalSolid
Masse atomique relative standard
[270]Configuration électronique
[Rn] 7s2 5f14 6d6Point de fusion
N/DPoint d’ébullition
N/DMasse volumique
4,07e+4 kg/m³États d’oxydation
+3, +4, +6, +8Électronégativité (Pauling)
N/DÉnergie d’ionisation (1re)
7,6 eVAnnée de découverte
1984Rayon atomique
126 pmDétails
Hassium is a synthetic transactinide element in group 8, below osmium. It is known only from atom-at-a-time production in heavy-ion reactions, and all confirmed isotopes are radioactive and short-lived. Its chemistry is important mainly because it tests whether very heavy elements still follow periodic trends despite strong relativistic effects. Experiments show behavior consistent with a heavy osmium analogue, especially in the formation of a volatile tetroxide.
Hassium does not occur naturally in the Earth’s crust. Hassium was first synthesized by German scientists at the GSI Center for Heavy Ion Research in Darmstadt, Germany in 1984 using the nuclear reaction 208Pb (58Fe, n) 265Hs (Fig. IUPAC.108.1). The element is named for Hassia (the Latin name for the German state of Hesse), whose former capital was Darmstadt [651], [652], [653]. Hassium is used in chemical and heavy element research.
Hassium was first produced by Peter Armbruster, Gottfried Münzenber and their team working at the Gesellschaft für Schwerionenforschung in Darmstadt, Germany in 1984. They bombarded atoms of lead-208 with ions of iron-58 with a device known as a linear accelerator. This produced atoms of hassium-265, an isotope with a half-life of about 2 milliseconds (0.002 seconds), and a free neutron. Hassium's most stable isotope, hassium-270, has a half-life of about 22 seconds. It decays into seaborgium-266 through alpha decay.
Its name is Latin "Hassias" meaning "Hess," from the German state. Discovered by Peter Armbruster, Gottfried Munzenber and co-workers at GSI in Darmstadt, Germany in 1984.
No macroscopic sample of hassium has been prepared, so its visible appearance is unknown. Calculations predict a dense metallic solid under ordinary conditions, but color, crystal form, and most bulk physical properties have not been observed directly.
Hassium has no commercial, medical, or industrial use. Its use is confined to nuclear and chemical research, where individual atoms are made to study superheavy-element stability, decay chains, and relativistic effects on chemical behavior. Chemical experiments with hassium are also used to test group 8 periodicity at the end of the known periodic table. The element is not available in quantities suitable for materials testing or applied technology.
Since only small amounts of hassium have ever been produced, it currently has no uses outside of basic scientific research.
The best-established chemical species is hassium tetroxide (HsO₄), formed in atom-at-a-time gas-phase experiments under oxidizing conditions. Its behavior is broadly comparable to osmium tetroxide (OsO₄), supporting the placement of hassium in group 8 and the accessibility of the +8 oxidation state. Other oxidation states and compounds are mainly predicted from theory or inferred by analogy with ruthenium and osmium. No isolable bulk hassium compound has been characterized.
See more information at the Hassium compound page.
Hassium isotopes are intensely radioactive on an atom-by-atom basis, decaying mainly by alpha emission and spontaneous fission, depending on the isotope. Because only a few atoms are produced, ordinary chemical toxicity has no practical relevance. The real hazards in hassium work come from accelerator operations, radioactive targets and products, recoil collection systems, and contamination control in specialized laboratories.
Hassium has no confirmed natural occurrence and no known environmental cycle. Atoms produced in laboratories decay rapidly, so environmental transport, bioaccumulation, and ecological effects have not been observed. If released as individual atoms or simple compounds, its chemistry would probably resemble that of a very heavy group 8 element, but this remains experimentally limited and environmentally irrelevant at present production scales.
Hassium has no commodity market, no industrial demand, and no practical supply chain. It is produced only in specialized nuclear laboratories by bombarding heavy actinide or lead targets with accelerated ions, yielding at most small numbers of atoms. The limiting factors are accelerator access, target preparation, detection efficiency, and isotope half-life rather than raw material price. There is no recycling or stockpiling of hassium as a usable material, because produced atoms decay during the experiment.
Formed by the bombardment of lead-208 with iron-58.
Hassium is not expected to persist as a primordial element because its known isotopes have half-lives far too short on geological or cosmic timescales. Superheavy nuclei in this mass region may be formed transiently in extreme neutron-rich nucleosynthesis, but no extraterrestrial hassium has been detected. Any such atoms would decay into lighter nuclides unless an unknown long-lived isotope existed.
- Hassium was named after Hesse, the German state where it was first synthesized.
- Its chemical study has been performed with single atoms carried through apparatus before they decay.
- The volatile tetroxide was central to confirming its group 8 character.
- Known hassium isotopes are identified largely through their decay chains.
- No weighed sample of hassium has ever existed.
Images
Propriétés
Propriétés physiques
- Rayon atomique (empirique)
- 126 pm Comparer : Rayon atomique (empirique) de tous les éléments →
- Masse volumique
- 4,07 × 104 kg/m³ Comparer : Masse volumique de tous les éléments →
Propriétés chimiques
- Affinité électronique
- 1,1 eV
- Énergie d’ionisation (1re)
- 7,6 eV Comparer : Énergie d’ionisation (1re) de tous les éléments →
- Énergie d’ionisation (2e)
- 18,200063 eV Comparer : Énergie d’ionisation (2e) de tous les éléments →
- Énergie d’ionisation (3e)
- 29,300101 eV Comparer : Énergie d’ionisation (3e) de tous les éléments →
- Énergie d’ionisation (4e)
- 37,70013 eV Comparer : Énergie d’ionisation (4e) de tous les éléments →
- Énergie d’ionisation (5e)
- 51,200176 eV Comparer : Énergie d’ionisation (5e) de tous les éléments →
- États d’oxydation
- +3, +4, +6, +8 Comparer : États d’oxydation de tous les éléments →
- Électrons de valence
- 8 Comparer : Électrons de valence de tous les éléments →
- Configuration électronique
- [Rn] 7s2 5f14 6d6
Propriétés thermodynamiques
N/D
Propriétés nucléaires
- Protons
- 108 Comparer : Protons de tous les éléments →
- Neutrons
- 161 Comparer : Neutrons de tous les éléments →
- Isotopes connus
- 18 Comparer : Isotopes connus de tous les éléments →
- Isotopes stables
- 0 Comparer : Isotopes stables de tous les éléments →
- Nombre de masse (isotope le plus stable)
- 270
- Isotope le plus stable
- Hs-269
- Année de découverte
- 1984
Abondance
N/D
Structure cristalline
N/D
Structure électronique
- Électrons par couche
- 2, 8, 18, 32, 32, 14, 2 Comparer : Électrons par couche de tous les éléments →
Identifiants
- Numéro CAS
- 54037-57-9 Comparer : Numéro CAS de tous les éléments →
- Symbole de terme
- 4
- InChI
- InChI=1S/Hs
- Clé InChI
- OBDWMWVOVYJOMI-UHFFFAOYSA-N
Configuration électronique Prédit
Hs: 5f¹⁴ 6d⁶ 7s²[Rn] 5f¹⁴ 6d⁶ 7s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 6d⁶ 7s²Modèle atomique
Les isotopes diffèrent par leur nombre de neutrons, leur masse et leur stabilité — pas par la configuration électronique de l’atome neutre.
Modèle atomique schématique, non à l’échelle.
Empreinte atomique
Spectre d’émission / d’absorption
Distribution isotopique
Aucun isotope stable.
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie |
|---|---|---|---|
| 273 Radioactif | 273,14168 ± 0,0004 | N/D | 1060 ms |
| 274 Radioactif | 274,1433 ± 0,00063 | N/D | 500 ms |
| 275 Radioactif | 275,14667 ± 0,00063 | N/D | 280 ms |
| 276 Radioactif | 276,14846 ± 0,00086 | N/D | 100 ms |
| 280 Radioactif | 280,159335 ± 0,000644 | N/D | 100 ms |
Phase / État
Données de phase ou d’état indisponibles
Spectres atomiques
Affichage de 10 sur 97. Tri par charge ionique croissante.
Niveaux répertoriés ?
| Ion | Charge | Niveaux |
|---|---|---|
| Hs I | 0 | 2 |
| Hs II | +1 | 2 |
| Hs III | +2 | 2 |
| Hs IV | +3 | 2 |
| Hs V | +4 | 2 |
| Hs VI | +5 | 2 |
| Hs VII | +6 | 2 |
| Hs VIII | +7 | 2 |
| Hs IX | +8 | 2 |
| Hs X | +9 | 2 |
Données de phase ou d’état indisponibles
Composés
Isotopes (5)
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie | Mode de désintégration | |
|---|---|---|---|---|---|
| 273 Radioactif | 273,14168 ± 0,0004 | N/D | 1060 ms | α ≈100%SF ? | |
| 274 Radioactif | 274,1433 ± 0,00063 | N/D | 500 ms | α ?SF ? | |
| 275 Radioactif | 275,14667 ± 0,00063 | N/D | 280 ms | α =100% | |
| 276 Radioactif | 276,14846 ± 0,00086 | N/D | 100 ms | α ?SF ? | |
| 280 Radioactif | 280,159335 ± 0,000644 | N/D | 100 ms | α ?SF ? |
Propriétés étendues
Rayons covalents (données étendues)
- Rayon covalent (Pyykkö)
- 134 pm
- Rayon covalent (Pyykkö, liaison double)
- 125 pm
- Rayon covalent (Pyykkö, liaison triple)
- 118 pm
Échelles de numérotation
- Mendeleev
- 62
Polarisabilité et dispersion
- Polarisabilité dipolaire
- 36 a.u.
- Polarisabilité dipolaire (incertitude)
- 4 a.u.
Catégories d’états d’oxydation
Données de référence avancées
Modes de désintégration des isotopes (33)
| Isotope | Mode | Intensité |
|---|---|---|
| 263 | A | 100% |
| 263 | SF | — |
| 264 | A | 70% |
| 264 | SF | 30% |
| 265 | A | 100% |
| 265 | SF | — |
| 266 | A | 76% |
| 266 | SF | 24% |
| 267 | A | 80% |
| 267 | SF | — |
Données complémentaires
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
Références (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
Références (1)
Références
(8)
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 Hassium.