Neptunium(III) fluoride

Neptunium(III) fluoride or neptunium trifluoride is a salt of neptunium and fluorine with the formula NpF₃.

Neptunium(III) fluoride

Names
IUPAC name Neptunium(III) fluoride
Other names Neptunium trifluoride
Identifiers
CAS Number	16852-37-2
3D model (JSmol)	Interactive image
ChemSpider	103872710
PubChem CID	13751216
CompTox Dashboard (EPA)	DTXSID701312245
InChI InChI=1S/Np.3FH/h;3*1H/q+3;;;/p-3 Y Key: ZBOLUSKWQLLYDC-UHFFFAOYSA-K
SMILES F[Np](F)F
Properties
Chemical formula	NpF3
Molar mass	294 g/mol
Appearance	Purple solid[1]
Structure
Crystal structure	Trigonal, hP8[1]
Space group	P63/mmc, No. 194[2]
Lattice constant	a = 0.7129 nm, c = 0.7288 nm
Lattice volume (V)	0.32077 nm3
Formula units (Z)	6
Thermochemistry
Heat capacity (C)	94 ± 3 J/mol·K[1]
Std molar entropy (S⦵298)	131 ± 3 J/mol·K[1]
Std enthalpy of formation (ΔfH⦵298)	−1529 ± 8 kJ/mol[1]
Gibbs free energy (ΔfG⦵)	−1461 ± 8 kJ/mol[1]
Related compounds
Other anions	Neptunium(III) chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

Neptunium(III) fluoride can be prepared by reacting neptunium dioxide with a gas mixture of hydrogen and hydrogen fluoride at 500 °C:^[1]

2 NpO₂ + H₂ + 6 HF → 2 NpF₃ + 4 H₂O