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