Potassium ferrooxalate, also known as potassium bisoxalatoferrate(II), is a salt with the formula [], sometimes abbreviated . The ferrooxalate anion (negative ion) is a transition metal complex, consisting of an atom of iron in the +2 oxidation state bound to two bidentate oxalate ions . The anion charge is balanced by two cations (positive ions) of potassium .J. Ladriere (1992): "Mössbauer study on the thermal decomposition of potassium tris (oxalato) ferrate(III) trihydrate and bis (oxalato) ferrate(II) dihydrate". Hyperfine Interactions, volume 70, issue 1, pages 1095–1098.
