Prof Tony Ford

*Author for correspondence. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Centre for Theoretical and Computational Chemistry, School of Chemistry, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa

Title: The Search for Some Blue-shifting Hydrogen-bonded Complexes

Abstract

In recent years the phenomenon of the blue-shifting hydrogen bond has received a great deal of attention, both experimentally and theoretically. Many systems which exhibit this phenomenon contain proton donors which possess one or more fluorine atoms in a region slightly remote from the primary site of interaction. In fact, several interpretations of the nature of this unusual type of molecular interaction have postulated such a structural feature as a necessary condition for the observation of this phenomenon. In an attempt to shed some light on this intriguing interaction, in this work we have examined two sets of hydrogen-bonded complexes, containing a common set of related proton acceptors (ammonia, water, hydrogen fluoride, phosphine, hydrogen sulphide and hydrogen chloride), and two proton donors (fluoroacetylene and fluoroform), which might be expected to exhibit the characteristic properties of blue-shifting hydrogen-bonded complexes, by means of a series of computational studies. We have carried out the calculations at the level of Møller-Plesset perturbation theory, using Dunning’s augmented correlation-consistent polarized valence triple zeta basis set. The results have been interpreted in terms of the perturbations of the molecular structures and vibrational spectra of the interacting monomers, and the dependence of the interaction energies on some relevant properties of the proton acceptors.