Tetrabromonickelate

The tetrabromonickelate anion contains a doubly-charged nickel atom (Ni²⁺) surrounded by four bromide ions in a tetrahedral arrangement. The formula is [NiBr₄]²⁻.

The anion combines with cations to form a series of salts called tetrabromonickelates. Strongly-coordinating solvents will displace one or more of the bromido ligands from the complex.^[1] Solvents that can dissolve tetrabromonickelate include acetone, acetonitrile, methyl ethyl ketone, and nitromethane.^[2]

In the visible absorption spectrum there is a strong absorption band termed ν₃ near 710 nm which is caused by an electronic transition from ³T₁(F) → ³T₁(P). Another strong absorption in the near infrared called ν₂ near 770 nm is due to the ³T₁(F) → ³A₂(F) transition.^[2]

^ Cite error: The named reference goodgame was invoked but never defined (see the help page).
^ ^a ^b Fine, Dwight A. (March 1965). "Tetrahedral Bromide Complexes of Nickel(II) in Organic Solvents". Inorganic Chemistry. 4 (3): 345–350. doi:10.1021/ic50025a019.

[goodgame-1] Cite error: The named reference goodgame was invoked but never defined (see the help page).

[fine-2] Fine, Dwight A. (March 1965). "Tetrahedral Bromide Complexes of Nickel(II) in Organic Solvents". Inorganic Chemistry. 4 (3): 345–350. doi:10.1021/ic50025a019.

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