HexacyanochromiumIII

HexacyanochromiumIII, also known as chromium(III) hexacyanide or chromium(III) ferrocyanide, is an inorganic compound with the chemical formula Cr3[Fe(CN)6]2. It is a coordination complex where chromium(III) ions are complexed with hexacyanoferrate(II) anions. This compound is typically encountered as a blue solid.

The structure involves chromium ions in a +3 oxidation state. The hexacyanoferrate(II) anion, often referred to as ferrocyanide, has the formula [Fe(CN)6]4-, with iron in a +2 oxidation state and cyanide ligands. The overall charge balance in the compound Cr3[Fe(CN)6]2 requires three chromium(III) ions (total +9 charge) to balance two ferrocyanide anions (total -8 charge), implying an additional charge to be accounted for, often leading to variations in nomenclature and precise structural descriptions depending on the source. However, the most common representation is as described.

HexacyanochromiumIII is generally insoluble in water. Its blue color is a characteristic property. It is not a commonly encountered compound in everyday applications and is primarily of interest in academic research related to coordination chemistry and inorganic synthesis. Its synthesis typically involves the reaction of chromium(III) salts with ferrocyanide salts under controlled conditions.