Uranium (III) bromide
| Crystal structure | ||||||||||
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| __ U 3+ __ Br - | ||||||||||
| Crystal system | ||||||||||
| Space group |
P 6 3 / m (No. 176) |
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| Lattice parameters |
a = 794.2 pm |
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| Coordination numbers |
U [9], Br [3] |
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| General | ||||||||||
| Surname | Uranium (III) bromide | |||||||||
| other names |
Uranium tribromide |
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| Ratio formula | UBr 3 | |||||||||
| Brief description |
red solid |
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| External identifiers / databases | ||||||||||
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| properties | ||||||||||
| Molar mass | 477.74 g mol −1 | |||||||||
| Physical state |
firmly |
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| Melting point |
730 ° C |
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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 . | ||||||||||
Uranium (III) bromide is a chemical compound made up of the elements uranium and bromine . It has the formula UBr 3 and belongs to the class of the bromides .
presentation
Uranium (III) bromide can be produced by the reaction of uranium (III) hydride and hydrogen bromide .
In contrast to the above reaction, the reduction of uranium (IV) bromide with hydrogen produces a product that contains less bromine than corresponds to the stoichiometric composition UBr 3 .
properties
Uranium (III) bromide is a red solid that melts at 730 ° C and looks greenish when melted. The structure of uranium (III) bromide corresponds to that of uranium (III) chloride . In this the uranium atoms are surrounded by nine bromine atoms each. The coordination polyhedron is a triple-capped, trigonal prism . It crystallizes in the hexagonal crystal system in the space group P 6 3 / m (No. 176) with the lattice parameters a = 794.2 pm and c = 444.1 pm and two formula units per unit cell .
Individual evidence
- ^ A b John H. Levy, John C. Taylor, Paul W. Wilson: "The Structure of Uranium Tribromide by Neutron Diffraction Profile Analysis", in: Journal of the Less Common Metals , 1975 , 39 (2), p. 265 -270 ( doi: 10.1016 / 0022-5088 (75) 90200-3 ).
- ^ A b c A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 1969.
- ↑ Entry on uranium compounds in the GESTIS substance database of the IFA , accessed on February 1, 2016 (JavaScript required)
- ↑ Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the specified labeling it falls under the group entry uranium compounds with the exception of those specified elsewhere in this Annex in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA) , accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
- ↑ The hazards emanating from radioactivity do not belong to the properties to be classified according to the GHS labeling.
- ↑ a b c Georg Brauer (ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3 , p. 1214.
literature
- Ingmar Grenthe, Janusz Drożdżynński, Takeo Fujino, Edgar C. Buck, Thomas E. Albrecht-Schmitt, Stephen F. Wolf: Uranium , 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. 253-698 ( doi : 10.1007 / 1-4020-3598-5_5 ).