Hassium (Hs)
transition-metalSolid
Peso atomico standard
[270]Configurazione elettronica
[Rn] 7s2 5f14 6d6Punto di fusione
N/DPunto di ebollizione
N/DDensità
4,07e+4 kg/m³Stati di ossidazione
+3, +4, +6, +8Elettronegatività (Pauling)
N/DEnergia di ionizzazione (1ª)
7,6 eVAnno della scoperta
1984Raggio atomico
126 pmDettagli
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.
Immagini
Proprietà
Fisiche
- Raggio atomico (empirico)
- 126 pm Confronta Raggio atomico (empirico) di tutti gli elementi →
- Densità
- 4,07 × 104 kg/m³ Confronta Densità di tutti gli elementi →
Chimiche
- Affinità elettronica
- 1,1 eV
- Energia di ionizzazione (1ª)
- 7,6 eV Confronta Energia di ionizzazione (1ª) di tutti gli elementi →
- Energia di ionizzazione (2ª)
- 18,200063 eV Confronta Energia di ionizzazione (2ª) di tutti gli elementi →
- Energia di ionizzazione (3ª)
- 29,300101 eV Confronta Energia di ionizzazione (3ª) di tutti gli elementi →
- Energia di ionizzazione (4ª)
- 37,70013 eV Confronta Energia di ionizzazione (4ª) di tutti gli elementi →
- Energia di ionizzazione (5ª)
- 51,200176 eV Confronta Energia di ionizzazione (5ª) di tutti gli elementi →
- Stati di ossidazione
- +3, +4, +6, +8 Confronta Stati di ossidazione di tutti gli elementi →
- Elettroni di valenza
- 8 Confronta Elettroni di valenza di tutti gli elementi →
- Configurazione elettronica
- [Rn] 7s2 5f14 6d6
Termodinamiche
N/D
Nucleari
- Protoni
- 108 Confronta Protoni di tutti gli elementi →
- Neutroni
- 161 Confronta Neutroni di tutti gli elementi →
- Isotopi noti
- 18 Confronta Isotopi noti di tutti gli elementi →
- Isotopi stabili
- 0 Confronta Isotopi stabili di tutti gli elementi →
- Numero di massa (isotopo più stabile)
- 270
- Isotopo più stabile
- Hs-269
- Anno della scoperta
- 1984
Abbondanza
N/D
Struttura cristallina
N/D
Struttura elettronica
- Elettroni per guscio
- 2, 8, 18, 32, 32, 14, 2 Confronta Elettroni per guscio di tutti gli elementi →
Identificativi
- Numero CAS
- 54037-57-9 Confronta Numero CAS di tutti gli elementi →
- Simbolo di termine
- 4
- InChI
- InChI=1S/Hs
- Chiave InChI
- OBDWMWVOVYJOMI-UHFFFAOYSA-N
Configurazione elettronica Previsto
Hs: 5f¹⁴ 6d⁶ 7s²[Rn] 5f¹⁴ 6d⁶ 7s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 6d⁶ 7s²Modello atomico
Gli isotopi modificano il numero di neutroni, la massa e la stabilità — non la configurazione elettronica di un atomo neutro.
Modello atomico schematico, non in scala.
Impronta atomica
Spettro di emissione / assorbimento
Distribuzione isotopica
Nessun isotopo stabile.
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita |
|---|---|---|---|
| 273 Radioattivo | 273,14168 ± 0,0004 | N/D | 1060 ms |
| 274 Radioattivo | 274,1433 ± 0,00063 | N/D | 500 ms |
| 275 Radioattivo | 275,14667 ± 0,00063 | N/D | 280 ms |
| 276 Radioattivo | 276,14846 ± 0,00086 | N/D | 100 ms |
| 280 Radioattivo | 280,159335 ± 0,000644 | N/D | 100 ms |
Fase / Stato
Dati sulla fase o sullo stato non disponibili
Spettri atomici
Sono visualizzati 10 di 97. Ordinamento per carica ionica crescente.
Livelli disponibili ?
| Ione | Carica | Livelli |
|---|---|---|
| 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 |
Dati sulla fase o sullo stato non disponibili
Composti
Isotopi (5)
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita | Modalità di decadimento | |
|---|---|---|---|---|---|
| 273 Radioattivo | 273,14168 ± 0,0004 | N/D | 1060 ms | α ≈100%SF ? | |
| 274 Radioattivo | 274,1433 ± 0,00063 | N/D | 500 ms | α ?SF ? | |
| 275 Radioattivo | 275,14667 ± 0,00063 | N/D | 280 ms | α =100% | |
| 276 Radioattivo | 276,14846 ± 0,00086 | N/D | 100 ms | α ?SF ? | |
| 280 Radioattivo | 280,159335 ± 0,000644 | N/D | 100 ms | α ?SF ? |
Proprietà estese
Raggi covalenti (dati estesi)
- Raggio covalente (Pyykkö)
- 134 pm
- Raggio covalente (Pyykkö, legame doppio)
- 125 pm
- Raggio covalente (Pyykkö, legame triplo)
- 118 pm
Scale di numerazione
- Mendeleev
- 62
Polarizzabilità e dispersione
- Polarizzabilità dipolare
- 36 a.u.
- Polarizzabilità dipolare (inc.)
- 4 a.u.
Categorie degli stati di ossidazione
Dati di riferimento avanzati
Modalità di decadimento degli isotopi (33)
| Isotopo | Modalità | Intensità |
|---|---|---|
| 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 | — |
Dati aggiuntivi
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
Riferimenti (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
Riferimenti (1)
Riferimenti
(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.