Neptunium tetrabromide

Neptunium tetrabromide

Names
Other names neptunium(IV) bromide
Identifiers
CAS Number	15608-32-9  Y
3D model (JSmol)	Interactive image
InChI InChI=1S/4BrH.Np/h4*1H;/q;;;;+4/p-4 Key: HUNTZSUKDFZQIP-UHFFFAOYSA-J
SMILES [Np+4].[Br-].[Br-].[Br-].[Br-]
Properties
Chemical formula	Br4Np
Molar mass	557 g·mol−1
Appearance	red-brown crystals
Density	5.5 g/cm3
Melting point	464 °C (867 °F; 737 K)
Related compounds
Related compounds	Uranium tetrabromide, Thorium tetrabromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Neptunium tetrabromide is a binary inorganic compound of neptunium metal and bromine with the chemical formula NpBr₄. ^{[1] [2] [3] [4]}

Synthesis

The compound can be prepared from the reaction of bromine with metallic neptunium:

Np + 2Br₂ → NpBr₄

Also, a reaction of aluminum bromide with neptunium(IV) oxide: ^{[5] [6]}

3NpO₂ + 4AlBr₃ → 3NpBr₄ + 2Al₂O₃

Physical properties

Neptunium tetrabromide forms red-brown hygroscopic crystals of monoclinic crystal system, spatial group P 2/c, ^{[7] [8]} cell parameters a = 1.089 nm, b = 0.874 nm, c = 0.705 nm, β = 95.19°, Z = 4. ^[9]

NpBr₄ is easily purified by sublimation in a vacuum. ^[10]

Chemical properties

Decomposes under strong heating to form neptunium tribromide:

2NpBr₄ → 2NpBr₃ + Br₂

With careful oxidation with antimony(III) oxide, the compound forms neptunium oxidibromide:

NpBr₄ + Sb₂O₃ → NpOBr₂ + 2SbOBr

References

1. "WebElements Periodic Table » Neptunium » neptunium tetrabromide". webelements.com. Retrieved 2 April 2024.
2. Stevens, J. L.; Jones, E. R.; Karraker, D. G. (15 February 1976). "Mössbauer spectra and magnetic susceptibility of neptunium tetrabromide" . The Journal of Chemical Physics . 64 (4): 1492–1494. Bibcode:1976JChPh..64.1492S. doi:10.1063/1.432366 . Retrieved 2 April 2024.
3. Brown, D.; Hill, J.; Rickard, C. E. F. (1 January 1970). "Preparation of actinide bromides and bromo-complexes by use of liquid boron tribromide or liquid bromine" . Journal of the Chemical Society A: Inorganic, Physical, Theoretical : 476–480. doi:10.1039/J19700000476. ISSN   0022-4944 . Retrieved 2 April 2024.
4. Yaws, Carl L. (6 January 2015). The Yaws Handbook of Physical Properties for Hydrocarbons and Chemicals: Physical Properties for More Than 54,000 Organic and Inorganic Chemical Compounds, Coverage for C1 to C100 Organics and Ac to Zr Inorganics. Gulf Professional Publishing. p. 740. ISBN   978-0-12-801146-1 . Retrieved 2 April 2024.
5. Fried, S. (1947). The Basic Dry Chemistry of Neptunium. Atomic Energy Commission. p. 10. Retrieved 2 April 2024.
6. Abstracts of Declassified Documents. Technical Information Division, Oak Ridge Directed Operations. 1947. p. 740. Retrieved 2 April 2024.
7. Morss, L. R.; Edelstein, Norman M.; Fuger, Jean (21 October 2010). The Chemistry of the Actinide and Transactinide Elements (Set Vol.1-6): Volumes 1-6. Springer Science & Business Media. p. 2416. ISBN   978-94-007-0211-0 . Retrieved 2 April 2024.
8. Kirk-Othmer Concise Encyclopedia of Chemical Technology, 2 Volume Set. John Wiley & Sons. 16 July 2007. p. 47. ISBN   978-0-470-04748-4 . Retrieved 2 April 2024.
9. The Chemical Thermodynamics of Actinide Elements and Compounds: The actinide halides. International Atomic Energy Agency. 1983. p. 162. Retrieved 2 April 2024.
10. Satya, Prakash (2013). Advanced Chemistry of Rare Elements. S. Chand Publishing. p. 684. ISBN   978-81-219-4254-6 . Retrieved 2 April 2024.