Ammonium oxalate monohydrate is the diammonium salt of oxalic acid. Its refined crystal structure has been investigated by three-dimensional diffraction studies. Influence of bivalent [Mn(II), Co(II), Ni(II)] and trivalent cations [Fe(III), Cr(III)] impurities on the growth rates of ammonium oxalate monohydrate crystals has been described. Its space group and unit cell parameters have been analyzed by neutron diffraction studies. Its IR spectra has been compared with that of isolated coal-solubilizing agent (CSA).
Ammonium oxalate monohydrate may be used to prepare an electrochemiluminescence (ECL) solution containing 1mM tris(2,2-bipyridyl)ruthenium(II) (Ru(bpy)32+) and 0.2mM ammonium oxalate monohydrate in a 0.1M ammonium acetate buffer at pH 5.0.