Americium (IV) oxide
| Crystal structure | |||||||||||||
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| __ On 4+ __ O 2− | |||||||||||||
| Crystal system | |||||||||||||
| Space group |
Fm 3 m (No. 225) |
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| Lattice parameters |
a = 533 pm |
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| Coordination numbers |
On [8], O [4] |
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| General | |||||||||||||
| Surname | Americium (IV) oxide | ||||||||||||
| other names |
Americium dioxide |
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| Ratio formula | AmO 2 | ||||||||||||
| Brief description |
black solid |
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| External identifiers / databases | |||||||||||||
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| properties | |||||||||||||
| Molar mass | 275.06 g mol −1 | ||||||||||||
| Physical state |
firmly |
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| density |
11.68 g cm −3 |
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| Melting point |
1000 ° C (decomposition) |
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| Hazard and safety information | |||||||||||||
 Radioactive |
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| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | |||||||||||||
Americium (IV) oxide is an oxide of the element americium . It has the molecular formula AmO 2 . Since all isotopes of americium are only artificially produced, americium (IV) oxide does not occur naturally. It is produced implicitly in nuclear reactors when uranium dioxide (UO 2 ) or plutonium dioxide (PuO 2 ) are irradiated with neutrons. Americium (IV) oxide is the main compound of this element. Almost all applications of this element are based on this connection.
presentation
The glowing of salts of americium is ideal for small quantities . In most cases, americium (III) oxalate (Am 2 (C 2 O 4 ) 3 ) or americium (III) nitrate (Am (NO 3 ) 3 ) are used. The americium (III) nitrate solutions are evaporated and then calcined to the oxide at 1000 ° C. The same procedure is used with precipitated americium (III) oxalate and then annealing at 900 ° C.
properties
Americium (IV) oxide is a black solid. It crystallizes in the cubic crystal system , the structure type is the CaF 2 type ( fluorite ) with the space group Fm 3 m (space group no. 225) and the coordination numbers Am [8], O [4].
use
Americium (IV) oxide (with the isotope 241 Am) is used as a source of ionizing radiation. Areas of application are fluorescence spectroscopy and as ionization smoke detectors .
In future radionuclide batteries , americium (IV) oxide could be used with the same radionuclide as fuel.
safety instructions
Classifications according to the CLP regulation are not available because they only include chemical hazard and play a completely subordinate role compared to the hazards based on radioactivity . The latter also only applies if the amount of substance involved is relevant.
Individual evidence
- ↑ a b c d Americium (IV) oxide at www.webelements.com.
- ↑ The hazards emanating from radioactivity do not belong to the properties to be classified according to the GHS labeling. With regard to other hazards, this substance has either not yet been classified or a reliable and citable source has not yet been found.
- ↑ Sherman Fried: The Preparation of Anhydrous Americium Compounds , in: J. Am. Chem. Soc. , 1951 , 73 (1), pp. 416-418 ( doi : 10.1021 / ja01145a135 ).
- ↑ Basic Elements of Static RTG's (PDF; 297 kB).
literature
- Wolfgang H. Runde, Wallace W. Schulz: Americium , in: Lester R. Morss, Norman M. Edelstein, Jean Fuger (Eds.): The Chemistry of the Actinide and Transactinide Elements , Springer, Dordrecht 2006; ISBN 1-4020-3555-1 , pp. 1265-1395 ( doi : 10.1007 / 1-4020-3598-5_8 ).