Rhenium(III) bromide
Names
Other names
  • Trirhenium nonabromide
  • Rhenium tribromide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.033.607 Edit this at Wikidata
EC Number
  • 236-984-5
  • InChI=1S/3BrH.Re/h3*1H;/q;;;+3/p-3
  • Br[Re](Br)Br
Properties
Re3Br9
Molar mass 425.92 g/mol
Appearance Black lustrous solid[1]
Melting point 500 °C (932 °F; 773 K)[2] (sublimes)
Reacts[1]
Solubility Sparingly soluble in ether and acetone, reacts with methanol and ammonia[1]
Structure
Trimeric
Thermochemistry
-164.4 kJ/mol[3]
Related compounds
Other anions
 Rhenium(III) chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Rhenium(III) bromide is a chemical compound with the formula Re3Br9. It is a black lustrous crystalline solid. This compound reacts with water to form rhenium(IV) oxide and is isostructural with rhenium(III) chloride.[1][4]

Preparation

This compound is prepared by the reaction of rhenium metal and bromine gas at 500 °C under nitrogen:[2]

6Re + 9Br2 → 2Re3Br9

If there is oxygen in the atmosphere, it will instead form rhenium(III) oxybromide.[2]

However, the most common method of producing this compound is by first reacting potassium hexabromorhenate(IV) with silver nitrate, which forms silver hexabromorhenite(IV), then this compound is heated to 600 °C to form rhenium(III) bromide.[1][3]

K2ReBr6 + 2AgNO3 → Ag2ReBr6 + 2KNO3
6Ag2ReBr6 → 12AgBr + 3Br2 + 2Re3Br9

An alternative method is a thermal decomposition of rhenium(V) bromide.

References

  1. ^ a b c d e Richard J. Thompson; Ronnie E. Foster; James L. Booker; Stephen J. Lippard (1967). "Rhenium(III) Bromide". In Muetterties, Earl (ed.). Inorganic Syntheses. Vol. 10. McGraw-Hill, Inc. pp. 58–61. doi:10.1002/9780470132418.ch9. ISBN 9780470132418.
  2. ^ a b c Harro Hagen; Adolf Sieverts (1933). "Rheniumtribromid". Zeitschrift für anorganische und allgemeine Chemie (in German). Verlag GmbH & Co. KGaA, Weinheim. 215 (1): 111–112. doi:10.1002/zaac.19332150114.
  3. ^ a b J. P. King; J. W. Cobble (1960). "The Thermodynamic Properties of Technetium and Rhenium Compounds. VII. Heats of Formation of Rhenium Trichloride and Rhenium Tribromide. Free Energies and Entropies". Journal of the American Chemical Society. 82 (9): 2111–2113. doi:10.1021/ja01494a005.
  4. ^ V. V. Ugarov (1971). "Electron-diffraction investigation of the structure of the Re3Br9 molecule". Journal of Structural Chemistry. 12 (2): 286–288. doi:10.1007/BF00739116. S2CID 100857081.
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