Potassium hexafluoronickelate(IV)

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Potassium hexafluoronickelate(IV)
K2NiF6.svg
Names
IUPAC name
potassium hexafluoronickelate(IV)
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.153.655 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 625-130-0
  • InChI=1S/6FH.2K.Ni/h6*1H;;;/q;;;;;;2*+1;+4/p-6
  • [K+].[K+].F[Ni-2](F)(F)(F)(F)F
Properties
K2NiF6
Molar mass 250.880
Hazards [1]
GHS labelling:
GHS-pictogram-skull.svg GHS-pictogram-exclam.svg GHS-pictogram-silhouette.svg
Danger
H302, H312, H317, H331, H350
P201, P261, P280, P304+P340, P405, P501
Safety data sheet (SDS) External SDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Potassium hexafluoronickelate(IV) is an inorganic compound with the chemical formula K
2
NiF
6
. It can be produced through the reaction of potassium fluoride, nickel dichloride, and fluorine.

It reacts violently with water, releasing oxygen. It dissolves in anhydrous hydrogen fluoride to produce a light-red solution. Potassium hexafluoronickelate(IV) decomposes at 350 °C, forming potassium hexafluoronickelate(III), nickel(II) fluoride, and fluorine: [2] [ better source needed ] [3]

Chemical structure of solid K2NiF6 as determined by X-ray crystallography. Mg2FeH6 from X-ray.jpg
Chemical structure of solid K2NiF6 as determined by X-ray crystallography.

Potassium hexafluoronickelate is a strong oxidant. It can turn chlorine pentafluoride and bromine pentafluoride into ClF+
6
and BrF+
6
, respectively: [4]

( X = Cl or Br , -60 °C , aHF = anhydrous hydrogen fluoride).

Potassium hexafluoronickelate decomposes at high temperatures to release fluorine gas; like terbium(IV) fluoride, the emitted fluorine is primarily monatomic rather than the typical diatomic. [5]

It adopts the structure seen for K2PtCl6 and Mg2FeH6. [6]

Related Research Articles

In chemistry, an interhalogen compound is a molecule which contains two or more different halogen atoms and no atoms of elements from any other group.

<span class="mw-page-title-main">Chlorine pentafluoride</span> Chemical compound

Chlorine pentafluoride is an interhalogen compound with formula ClF5. This colourless gas is a strong oxidant that was once a candidate oxidizer for rockets. The molecule adopts a square pyramidal structure with C4v symmetry, as confirmed by its high-resolution 19F NMR spectrum. It was first synthesized in 1963.

<span class="mw-page-title-main">Nickel(II) fluoride</span> Chemical compound

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

<span class="mw-page-title-main">Cobalt(III) fluoride</span> Chemical compound

Cobalt(III) fluoride is the inorganic compound with the formula CoF3. Hydrates are also known. The anhydrous compound is a hygroscopic brown solid. It is used to synthesize organofluorine compounds.

<span class="mw-page-title-main">Iron(III) fluoride</span> Chemical compound

Iron(III) fluoride, also known as ferric fluoride, are inorganic compounds with the formula FeF3(H2O)x where x = 0 or 3. They are mainly of interest by researchers, unlike the related iron(III) chlorides. Anhydrous iron(III) fluoride is white, whereas the hydrated forms are light pink.

<span class="mw-page-title-main">Hydrogen fluoride</span> Chemical compound

Hydrogen fluoride (fluorane) is an inorganic compound with the chemical formula HF. This colorless gas or liquid is the principal industrial source of fluorine, often as an aqueous solution called hydrofluoric acid. It is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers, e.g. polytetrafluoroethylene (PTFE). HF is widely used in the petrochemical industry as a component of superacids. Hydrogen fluoride boils at near room temperature, much higher than other hydrogen halides.

<span class="mw-page-title-main">Selenium tetrafluoride</span> Chemical compound

Selenium tetrafluoride (SeF4) is an inorganic compound. It is a colourless liquid that reacts readily with water. It can be used as a fluorinating reagent in organic syntheses (fluorination of alcohols, carboxylic acids or carbonyl compounds) and has advantages over sulfur tetrafluoride in that milder conditions can be employed and it is a liquid rather than a gas.

<span class="mw-page-title-main">Manganese(IV) fluoride</span> Chemical compound

Manganese tetrafluoride, MnF4, is the highest fluoride of manganese. It is a powerful oxidizing agent and is used as a means of purifying elemental fluorine.

<span class="mw-page-title-main">Iridium(V) fluoride</span> Chemical compound

Iridium(V) fluoride, IrF5, is a chemical compound of iridium and fluorine. A highly reactive yellow low melting solid, it has a tetrameric structure, Ir4F20, which contains octahedrally coordinated iridium atoms. This structure is shared with RuF5 and OsF5. It can be prepared by the controlled decomposition of IrF6 or the reduction of IrF6 with silicon powder or H2 in anhydrous HF.

<span class="mw-page-title-main">Tin(IV) fluoride</span> Chemical compound

Tin(IV) fluoride is a chemical compound of tin and fluorine with the chemical formula SnF4 and is a white solid with a melting point above 700 °C.

<span class="mw-page-title-main">Tetrafluoroammonium</span>

The tetrafluoroammonium cation is a positively charged polyatomic ion with chemical formula NF+
4
. It is equivalent to the ammonium ion where the hydrogen atoms surrounding the central nitrogen atom have been replaced by fluorine. Tetrafluoroammonium ion is isoelectronic with tetrafluoromethane CF
4
, trifluoramine oxide ONF
3
and the tetrafluoroborate BF
4
anion.

Nitrogen pentafluoride (NF5) is a theoretical compound of nitrogen and fluorine that is hypothesized to exist based on the existence of the pentafluorides of the atoms below nitrogen in the periodic table, such as phosphorus pentafluoride. Theoretical models of the nitrogen pentafluoride molecule are either a trigonal bipyramidal covalently bound molecule with symmetry group D3h, or NF+
4
F, which would be an ionic solid.

<span class="mw-page-title-main">Neptunium(VI) fluoride</span> Chemical compound

Neptunium(VI) fluoride (NpF6) is the highest fluoride of neptunium, it is also one of seventeen known binary hexafluorides. It is an orange volatile crystalline solid. It is relatively hard to handle, being very corrosive, volatile and radioactive. Neptunium hexafluoride is stable in dry air but reacts vigorously with water.

<span class="mw-page-title-main">Fluorine azide</span> Chemical compound

Fluorine azide or triazadienyl fluoride is a yellow green gas composed of nitrogen and fluorine with formula FN3. It is counted as an interhalogen compound, as the azide functional group is termed a pseudohalogen. It resembles ClN3, BrN3, and IN3 in this respect. The bond between the fluorine atom and the nitrogen is very weak, leading to this substance being very unstable and prone to explosion. Calculations show the F–N–N angle to be around 102° with a straight line of 3 nitrogen atoms.

The fluoronickelates are a class of chemical compounds containing an anion with nickel at its core, surrounded by fluoride ions which act as ligands. This makes it a fluoroanion. The nickel atom can be in a range of oxidation states from +2, +3 to +4. The hexafluoronickelate(IV)2− ion NiF62− contains nickel in the maximal +4 state, and is in octahedral coordination by the fluoride atoms. It forms a commercially available salt Potassium hexafluoronickelate(IV) K2NiF6. Solid double salts can also contain tetrafluoronickelate NiF4 eg K2NiF4.

<span class="mw-page-title-main">Chlorine trifluoride oxide</span> Chemical compound

Chlorine oxide trifluoride or chlorine trifluoride oxide is a corrosive liquid molecular compound with formula ClOF3. It was developed secretly as a rocket fuel oxidiser.

<span class="mw-page-title-main">Praseodymium(IV) fluoride</span> Chemical compound

Praseodymium(IV) fluoride (also praseodymium tetrafluoride) is a binary inorganic compound, a highly oxidised metal salt of praseodymium and fluoride with the chemical formula PrF4. It forms light yellow crystals.

Nickel(III) fluoride is the chemical compound with the formula NiF3. It is an ionic compound of nickel and fluorine.

<span class="mw-page-title-main">Protactinium(V) fluoride</span> Chemical compound

Protactinium(V) fluoride is a fluoride of protactinium, with the chemical formula PaF5.

References

  1. "Potassium Hexafluoronickelate(IV)". American Elements . Retrieved December 19, 2018.
  2. (in Chinese)张青莲. 《无机化学丛书》第九卷:锰分族、铁系、铂系. 北京: 科学出版社. pp. P333. ISBN   7-03-002238-6.
  3. Stein, Lawrence; Neil, John M.; Alms, Gregory R. (November 1969). "Properties of potassium hexafluoronickelates(III) and -(IV). Absorption spectra of nickel(III) and -(IV) in hydrogen fluoride solutions". Inorganic Chemistry. 8 (11): 2472–2476. doi:10.1021/ic50081a045. ISSN   0020-1669.
  4. Schroer, Thorsten; Christe, Karl O. (2001). "Novel Synthesis of ClF6+ and BrF6+ Salts". Inorganic Chemistry. 40 (10): 2415–9. doi:10.1021/ic001024. PMID   11327921.
  5. Rau, J. V.; Chilingarov, N. S.; Leskiv, M. S.; Sukhoverkhov, V. F.; Rossi Albertini, V.; Sidorov, L. N. (August 2001). "Transition and rare earth metal fluorides as thermal sources of atomic and molecular fluorine". Le Journal de Physique IV. 11 (PR3): Pr3–109–Pr3-113. doi:10.1051/jp4:2001314.
  6. Taylor, J. C. "A comparison of profile decomposition and Rietveld methods for structurtal refinement with powder diffraction data" Zeitschrift für Kristallographie 1987, volume 181, p151-160.