Synonyms: Nickelate(4-), ((P,P',P''-((nitrilo-kappaN)tris(methylene))tris(phosphonato-kappaO))(6-))-, sodium (1:4), (T-4)-;Tetrasodium nickelous nitrilotri(methylenephosphonate);Nickelate(4-), ((((nitrilo-kappaN)tris(methylene))tris(phosphonato-kappaO))(6-))-, tetrasodium, (T-4)-;Tetrasodium (((nitrilotris(methylene))tris(phosphonato))(6-)-N,O,O'',O'''nickelate(4-))