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

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 Added by Cristian G. Sanchez
 Publication date 1997
  fields Physics
and research's language is English




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A series of calculations on the energetics of complexation of alkaline metals with 1,10-phenanthroline are presented. It is an experimental fact that the ordering of the free energy of transfer across the water - 1,2-dichloroethane interphase is governed by the charge / size ratio of the diferent cations; the larger cations showing the lower free energy of transfer. This ordering of the free 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 phen the free energy of transfer is governed by the stability of the PHEN/M $^{+}$complex, which explains the observed tendency from a theoretical point of view.



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