Curium (III) bromide
| Crystal structure | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||
| __ Cm 3+ __ Br - | ||||||||||
| Crystal system | ||||||||||
| Space group |
Cmcm (No. 63) |
|||||||||
| Lattice parameters |
a = 405 pm |
|||||||||
| General | ||||||||||
| Surname | Curium (III) bromide | |||||||||
| other names |
Curium tribromide |
|||||||||
| Ratio formula | CmBr 3 | |||||||||
| Brief description |
colorless solid |
|||||||||
| External identifiers / databases | ||||||||||
|
||||||||||
| properties | ||||||||||
| Molar mass | depending on the isotope: 479–493 g · mol −1 | |||||||||
| Physical state |
firmly |
|||||||||
| density |
6.87 g cm −3 |
|||||||||
| Melting point |
625 ° C |
|||||||||
| Hazard and safety information | ||||||||||
 Radioactive |
||||||||||
|
||||||||||
| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | ||||||||||
Curium (III) bromide is a bromide of the artificial element and actinide curium with the empirical formula CmBr 3 . In this salt , curium occurs in the +3 oxidation state. Since all isotopes of curium are only artificially produced, it has no natural occurrence.
presentation
Curium (III) bromide can be obtained by reacting curium (III) chloride with ammonium bromide at 400–450 ° C under a hydrogen atmosphere.
Another possibility is the reaction between curium (III) oxide and hydrobromic acid at 600 ° C.
properties
Curium (III) bromide is a colorless ion compound consisting of Cm 3+ and Br - ions. It crystallizes in the orthorhombic crystal system in the space group Cmcm (space group no. 63) with the lattice parameters a = 405 pm , b = 1266 pm and c = 912 pm and four formula units per unit cell . Its crystal structure is isotypic with plutonium (III) bromide .
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
- ↑ Gregg J. Lumetta, Major C. Thompson, Robert A. Penneman, P. Gary Eller: Curium , in: Lester R. Morss, Norman M. Edelstein, Jean Fuger (ed.): The Chemistry of the actinides and transactinide element element , Springer, Dordrecht 2006; ISBN 1-4020-3555-1 , pp. 1397-1443 ( doi : 10.1007 / 1-4020-3598-5_9 ).
- ↑ Gmelin's Handbook of Inorganic Chemistry , System No. 71, Transurane, Part C, p. 149.
- ^ A b John H. Burns, JR Peterson, JN Stevenson: Crystallographic Studies of some Transuranic Trihalides: 239 PuCl 3 , 244 CmBr 3 , 249 BkBr 3 and 249 CfBr 3 , in: Journal of Inorganic and Nuclear Chemistry , 1975 , 37 ( 3), pp. 743-749 ( doi : 10.1016 / 0022-1902 (75) 80532-X ).
- ↑ 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.
- ↑ a b L. B. Asprey, TK Keenan, FH Kruse: Crystal Structures of the Trifluorides, Trichlorides, Tribromides, and Triiodides of Americium and Curium , in: Inorg. Chem. , 1965 , 4 (7), pp. 985-986 ( doi : 10.1021 / ic50029a013 ).
literature
- Gregg J. Lumetta, Major C. Thompson, Robert A. Penneman, P. Gary Eller: Curium , 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. 1397-1443 ( doi : 10.1007 / 1-4020-3598-5_9 ).