Neptunium(IV) phosphide

Neptunium(IV) phosphide is a binary inorganic compound of neptunium metal and phosphorus with the chemical formula Np₃P₄.^[1]

Neptunium(IV) phosphide

Identifiers
CAS Number	111117-76-1 Y
3D model (JSmol)	Interactive image
InChI InChI=1S/3Np.4P Key: BLKYGPPFNRPFDX-UHFFFAOYSA-N
SMILES [Np].[Np].[Np].[P].[P].[P].[P]
Properties
Chemical formula	Np3P4
Molar mass	835 g·mol−1
Appearance	black crystals
Solubility in water	insoluble
Related compounds
Related compounds	Neptunium(III) phosphide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

Neptunium(IV) phosphide can be formed from the fusion of stoichiometric amounts of neptunium and red phosphorus in an evacuated and sealed quartz tube at 750 °C:^[2][3]

3Np + 4P → Np₃P₄

Physical properties

Neptunium(IV) phosphide forms black crystals of cubic crystal system, spatial group I 43d. Isostructural with Th₃P₄.^[4]

It does not dissolve in water.

Chemical properties

The compound reacts with concentrated HCl to give a green solution:^[5]

Np₃P₄ + 12HCl → 3NpCl₄ + 4PH₃