Formation of Mononuclear Rhodium(III) Sulfates: ~(103)Rh and ~(17)O NMR Study

摘要

It was shown that the monomeric rhodium sulfate complexes [Rh(H2O)4(SO4)]~+, trans-[Rh(H2O)2(SO4)2]~-, cis-[Rh(H2O)2(SO4)2]~-, and [Rh(SO4)3]~(3-) were not predominant forms in aqueous solutions. The ~(103)Rh NMR chemical shifts of the complexes were assigned, and the conditions for their formation in solutions, concentration parameters, and acidity at which the fraction of the monomers was maximal were determined. The constants of formation of the complexes and ion pair (IP) were estimated: K_(IP)= 8 + 3.5, K1≈ 8, K_(2trans)≈1, K_(2cis)≈1, and K3≈2.