Carbonato-phosphate

Simpler Ligands. Composition data (Table I) of the sea include aquo, halo (Cl", Br", F"), carbonato, and sulfato complexes. Since the pH of our average ocean is 8.1, hydroxo complexes would also be important, as might be phosphate complexes. Except for the halides, ligands important to marine science are almost routinely overlooked by most coordination chemists. Fortunately there are exceptions, as noted from the papers in this volume. 

In sununaiy, the aqueous speciation of U in solutions that are believed to be representative of the relatively oxidizing and reducing groundwaters of the Tono region is dominated by U(OH)4(aq) under reducing conditions, and by the uranyl mono-, di- and tri-carbonato complexes, and (or) U02(0H)3, under relatively oxidizing conditions. Uranous fluoride or phosphate complexes, or their uranyl counterparts, are important in these respective solutions only if pH is less than 6 or 7. 

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