Hassium (Hs)
transition-metalSolid
Standard Atomic Weight
[270]Electron configuration
[Rn] 7s2 5f14 6d6Melting point
N/ABoiling point
N/ADensity
4.070000e+4 kg/m³Oxidation states
+3, +4, +6, +8Electronegativity (Pauling)
N/AIonization energy (1st)
Discovery year
1984Atomic radius
126 pmDetails
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.
Images
Properties
Physical
Chemical
Thermodynamic
N/A
Nuclear
Abundance
N/A
Reactivity
N/A
Crystal Structure
N/A
Electronic Structure
Identifiers
Electron Configuration Predicted
Hs: 5f¹⁴ 6d⁶ 7s²[Rn] 5f¹⁴ 6d⁶ 7s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 6d⁶ 7s²Atomic model
Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.
Schematic atomic model, not to scale.
Atomic Fingerprint
Emission / Absorption Spectrum
Isotope Distribution
No stable isotopes.
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|---|---|---|
| 273 Radioactive | 273.14168 ± 0.0004 | N/A | 1060 ms |
| 274 Radioactive | 274.1433 ± 0.00063 | N/A | 500 ms |
| 275 Radioactive | 275.14667 ± 0.00063 | N/A | 280 ms |
| 276 Radioactive | 276.14846 ± 0.00086 | N/A | 100 ms |
| 280 Radioactive | 280.159335 ± 0.000644 | N/A | 100 ms |
Phase / State
Phase/state data not available
Atomic Spectra
Showing 10 of 97 Atomic Spectra. Sorted by ion charge (ascending).
Levels Holdings ?
| Ion | Charge | Levels |
|---|---|---|
| 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 |
Phase/state data not available
Compounds
Isotopes (5)
| Mass number | Atomic mass (u) | Natural abundance | Half-life | Decay mode | |
|---|---|---|---|---|---|
| 273 Radioactive | 273.14168 ± 0.0004 | N/A | 1060 ms | α ≈100%SF ? | |
| 274 Radioactive | 274.1433 ± 0.00063 | N/A | 500 ms | α ?SF ? | |
| 275 Radioactive | 275.14667 ± 0.00063 | N/A | 280 ms | α =100% | |
| 276 Radioactive | 276.14846 ± 0.00086 | N/A | 100 ms | α ?SF ? | |
| 280 Radioactive | 280.159335 ± 0.000644 | N/A | 100 ms | α ?SF ? |
Extended Properties
Covalent Radii (Extended)
Numbering Scales
Polarizability & Dispersion
Oxidation State Categories
Advanced Reference Data
Isotope Decay Modes (33)
| Isotope | Mode | Intensity |
|---|---|---|
| 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 | — |
Additional Data
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
References (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
References (1)
References
(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.