Ion Pair Association Of Complexes Of La3+ And Nd3+ With Br- And No3 - In N,n-dimethylacetamide

Abstract

The formation constants and the respective variations of enthalpy were obtained by means of calorimetric titration of the lanthanides La3+ and Nd3+ with bromide and nitrate in N,N-dimethylacetamide. These thermochemical data were calculated for the 1:1 and 1:2 species which are less stable than the corresponding species obtained with chloride. The order of stability Cl- > Br->NO3 - was established for both species of La3+, and the order Br->Cl->LNO3 - for 1:1 species of Nd3+. NdCl2 + and NdBr2 + species were not detected. Our results support the view that the metal-anion interactions involve inner sphere species. © 1982.