Facilitated alkali ion transfer at the water/1,2-dichloroethane interphase: Ab-initio calculations concerning alkaline metal-1,10-phenanthroline complexes

C.G. SÁNCHEZ; S.A. DASSIE; A.M.BARUZZI; E.P.M. LEIVA

ELSEVIER

Lugar: Amsterdam; Año: 1998 vol. 451 p. 111 - 111

series of calculations on the energetics of complexation of alkaline metal cations with 1,10-phenanthroline are presented. It is an experimental fact that the ordering of the Gibbs energy of transfer across the water1,2-dichloroethane interphase is governed by the charge:size ratio of the different cations; the larger cations showing the lower Gibbs energy of transfer. This ordering of the Gibbs energies of transfer is reverted in the presence of 1,10-phenanthroline in the organic phase. We have devised a thermodynamic cycle for the transfer process and, by means of ab initio calculations, have drawn the conclusion that in the presence of phenanthroline the Gibbs energy of transfer is governed by the stability of the phenanthroline:M complex, which explains the observed tendency from a theoretical point of view.