tetradecaammonium [[(phosphonatomethyl)imino]bis[ethylene[(phosphonatomethyl)imino]ethylenenitrilobis(methylene)]]tetrakisphosphonate

[[(Phosphonomethyl)imino]bis[2,1-ethanediyl[(phosphonomethyl)imino](2,1-ethanediyl)(nitrilo)bismethylene]]tetrakisphosphonic acid tetradecaammonium salt