Cation inorganic ligands

The guest cations hitherto examined cover broadly uni- to trivalent and inorganic to organic ions that include alkali, alkaline earth, heavy and transition metal ions, as well as (ar)alkyl ammonium and diazonium ions. As to the complex stoichiometry between cation and ligand, both 1 1 stoichiometric and 1 2 sandwich complexes are analyzed. The solvent systems employed also vary widely from protic and aprotic homogeneous phase to binary-phase solvent extraction. 

Neutral organoarsenic compounds of the type R3ASO are widely used for extraction of uranium and other valuable elements from aqueous solutions The photoluminescence method has been applied to study the kinetics of formation of complexes of uranyl cations with organic and inorganic ligands ... 

Sorption of trace elements onto soil components is greatly affected by pH, ionic factors, nature of the sorbents, redox reactions, and so on, but the sorption of elements in cationic form differs greatly from that of elements in anionic form. The presence of organic and inorganic ligands (including nutrients) in soil environments has a very important role in the sorption-desorption processes of trace elements. 

Most competitive sorption studies have been carried out adding the ions contemporaneously. In natural environments, however, it is more likely that the ions will come in contact with a sorbent sequentially (i.e., the solid is exposed to one ion first, with the second ion coming in contact with a solid at a later time). The sorption of trace elements in cationic or anionic form is strongly influenced by the order of addition of organic and inorganic ligands and trace elements on the sorbents. 

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