Neptunium(III) bromide

Neptunium(III) bromide
Identifiers
CAS Number	20730-39-6 ;
3D model (JSmol)	Interactive image ;
	InChI InChI=1S/3BrH.Np/h3*1H;/q;;;+3/p-3 Key: HVGILCLFCSGPEI-UHFFFAOYSA-K;
	SMILES [Np+3].[Br-].[Br-].[Br-];
Properties
Chemical formula	Br3Np
Molar mass	477 g·mol−1
Appearance	green solid
Density	6.62 g·cm−3
Structure
Crystal structure	α-NpBr3: hexagonal ; β-NpBr3: orthorhombic
Space group	α-NpBr3: P63/m (No. 176); β-NpBr3: Ccmm (No. 63)
Lattice constant	a = 791.7 pm (α), 411 pm (β), b = 791.7 pm (α), 1265 pm (β), c = 438.2 pm (α), 915 pm (β)
Related compounds
Other anions	neptunium(III) fluoride ; neptunium(III) chloride ; neptunium(III) iodide
Other cations	uranium(III) bromide ; plutonium(III) bromide
Related compounds	neptunium(IV) bromide
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Last updated August 19, 2025

Neptunium(III) bromide is a bromide of neptunium, with the chemical formula of NpBr₃.

Preparation

Neptunium(III) bromide can be prepared by reacting neptunium dioxide and aluminium bromide:^[3]

6 NpO₂ + 8 AlBr₃ → 6 NpBr₃ + 4 Al₂O₃ + 3 Br₂

Properties

Neptunium(III) bromide is a green solid. It can crystallize in two crystal systems:

α-NpBr₃ is hexagonal with lattice parameters a = 791.7 pm and c = 438.2 pm.^[2] It has the same structure as uranium trichloride.

β-NpBr₃ is orthorhombic with lattice parameters a = 411 pm, b = 1265 pm and c = 915 pm.^[2] It has the same structure as the bromides from plutonium to californium.

Neptunium(III) bromide also has a green hexahydrate, which is monoclinic.^[3]

Reactions

At 425 °C, neptunium(III) bromide bromide can be further brominated by bromine to form neptunium(IV) bromide.^[2]

2 NpBr₃ + Br₂ → 2 NpBr₄

References

↑ Holleman, Arnold Frederik; Wiberg, Egon (2001), Wiberg, Nils (ed.), Inorganic Chemistry, translated by Eagleson, Mary; Brewer, William, San Diego/Berlin: Academic Press/De Gruyter, p. 1969, ISBN 0-12-352651-5
1 2 3 4 Gmelins Handbuch der anorganischen Chemie , System No. 71, Transurane, Teil C, S. 148–150.
1 2 Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: Handbuch der Präparativen Anorganischen Chemie. 3., umgearbeitete Auflage. Band II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3, S. 1268.

External reading

Yoshida, Zenko; Johnson, Stephen G.; Kimura, Takaumi; Krsul, John R. (2006), Morss, Lester R.; Edelstein, Norman M.; Fuger, Jean (eds.), "Neptunium" , The Chemistry of the Actinide and Transactinide Elements, Dordrecht: Springer Netherlands, pp. 699–812, doi:10.1007/1-4020-3598-5_6, ISBN 978-1-4020-3555-5 , retrieved 2023-12-23
Keller, C. (1969), "Die Chemie des Neptuniums" , Anorganische Chemie, Fortschritte der Chemischen Forschung (in German), vol. 13/1, Berlin/Heidelberg: Springer-Verlag, pp. 1–124, doi:10.1007/bfb0051170, ISBN 978-3-540-04488-8 , retrieved 2023-12-23

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[HOWI_1969-1] Holleman, Arnold Frederik; Wiberg, Egon (2001), Wiberg, Nils (ed.), Inorganic Chemistry, translated by Eagleson, Mary; Brewer, William, San Diego/Berlin: Academic Press/De Gruyter, p. 1969, ISBN 0-12-352651-5

[Gmelin-2] 1 2 3 4 Gmelins Handbuch der anorganischen Chemie , System No. 71, Transurane, Teil C, S. 148–150.

[brauer-3] 1 2 Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: Handbuch der Präparativen Anorganischen Chemie. 3., umgearbeitete Auflage. Band II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3, S. 1268.

[1]

[2]

[3]