MECHANISM FOR THE EFFECTS OF MONO-VALENT CATIONS ON ~(23)Na NMR

The effects of mono-valent cations, Li~+, K~+, Rb~+, Cs~+ and NH_4~+, on ~(23)Na NMR were investigated. It was found that the chemical shifts for Na~+ signal shifted downfield with the increase in the relative amounts of monovalent cations. It was suggested that mono-valent cations had competition coordination with Na~+ for Dy(PPP)_2~(7-).