Nickel(II) fluoride

Nickel(II) fluoride

Names
IUPAC name Nickel(II) fluoride
Identifiers
CAS Number	10028-18-9 Y
3D model (JSmol)	Interactive image
ChemSpider	23210 Y
ECHA InfoCard	100.030.053
EC Number	233-071-3
PubChem CID	24825
RTECS number	QR6825000
UNII	69NBB20493 N
InChI InChI=1S/2FH.Ni/h2*1H;/q;;+2/p-2 Y Key: DBJLJFTWODWSOF-UHFFFAOYSA-L Y InChI=1S/2FH.Ni/h2*1H;/q;;+2/p-2 Key: DBJLJFTWODWSOF-NUQVWONBAA Key: DBJLJFTWODWSOF-UHFFFAOYSA-L
SMILES F[Ni]F
Properties
Chemical formula	NiF2
Molar mass	96.6902 g/mol
Appearance	Yellowish to green tetragonal crystals
Density	4.72 g/cm3
Melting point	1,474 °C (2,685 °F; 1,747 K)
Boiling point	1,750 °C (3,180 °F; 2,020 K)
Solubility in water	4 g/100 mL
Solubility	insoluble in alcohol, ether
Magnetic susceptibility (χ)	+2410.0·10−6 cm3/mol
Structure
Crystal structure	Rutile
Coordination geometry	Nickel: Octahedral Oxygen: Trigonal planar
Hazards
Safety data sheet	External MSDS
Related compounds
Other anions	Nickel(II) chloride Nickel(II) bromide Nickel(II) iodide
Other cations	Cobalt(II) fluoride Copper(II) fluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Nickel(II) fluoride is the chemical compound with the formula NiF₂. Its is an ionic compound of nickel and fluorine and forms yellowish to green tetragonal crystals. Unlike many fluorides, NiF₂ is stable in air.

NiF₂ comprises the passivating surface that forms on nickel alloys (e.g. monel) in the presence of hydrogen fluoride or elemental fluorine, which is why nickel and its alloys are among the few materials that can be used to store or transport these fluorine compounds. NiF₂ is also used as a catalyst for the synthesis of chlorine pentafluoride.

NiF₂ is prepared by treatment of anhydrous nickel(II) chloride with fluorine at 350 °C:

The corresponding reaction of cobalt(II) chloride results in oxidation of the cobalt, whereas nickel remains in the +2 oxidation state after fluorination because its +3 oxidation state is less stable. Chloride is more easily oxidized than nickel(II). This is a typical halogen displacement reaction, where a halogen plus a less active halide makes the less active halogen and the more active halide.

Nickel(II) fluoride is also produced when fluorine reacts with nickel metal.

A melt of NiF₂ and KF reacts to give the green compound K₂[NiF₄]. The structure of this material is closely related to some superconducting oxide materials.

Nickel(II) fluoride reacts with strong bases to make nickel(II) hydroxide, a green colored compound.

NiF₂ + 2 NaOH → Ni(OH)₂ + 2 NaF