Iron(III) acetate

Basic iron acetate forms on treating aqueous solutions of iron(III) sources with acetate salts. It is slowly soluble in water and poorly soluble in acetic acid. A typical precursor is freshly precipitated iron oxide/hydroxide, which is halide-free. Early work showed that the cation is trinuclear. The Fe centres are equivalent, each being octahedral, being bound to six oxygen ligands, including a triply bridging oxide at the center of the equilateral triangle. The compound was an early example of a molecular complex of iron that features an oxide ligand. The cation has idealized D3h symmetry. == Reactions ==

The terminal aqua ligands on the trimetallic framework can be substituted with other ligands, such as pyridine and dimethylformamide. Many different salts are known by exchanging the anion, e.g. [Fe3(μ3-O)(OAc)6(H2O)3]Cl. Reduction of the cation affords the neutral mixed-valence derivative that contains one ferrous and two ferric centers. == Related compounds ==

Chromium(III), ruthenium(III), vanadium(III), manganese(III) and rhodium(III) form analogous compounds. Iron(III) acetate (lacking the oxo ligand) has been claimed as a red coloured compound from the reaction of silver acetate and iron(III) chloride. == Uses ==

Materials prepared by heating iron, acetic acid, and air, loosely described as basic iron acetates, are used as dyes and mordants. Iron acetate is used in ebonising, which is a process for darkening wood, giving it an appearance similar to ebony. ==See also==