Anomalously strong effect of the ion sign on the thermochemistry of hydrogen bonded aqueous clusters of identical chemical composition

Alexey B Nadykto; Fangqun Yu; Anas Al Natsheh

doi:10.3390/ijms10020507

Anomalously strong effect of the ion sign on the thermochemistry of hydrogen bonded aqueous clusters of identical chemical composition

Int J Mol Sci. 2009 Feb;10(2):507-517. doi: 10.3390/ijms10020507. Epub 2009 Feb 5.

Authors

Alexey B Nadykto¹, Fangqun Yu¹, Anas Al Natsheh²

Affiliations

¹ Atmospheric Sciences Research Center, State University of New York at Albany, 251 Fuller Rd., Albany 12203, NY, USA.
² Kajaani University of Applied Sciences, Kuntokatu 5, 87101 Kajaani, Finland.

Abstract

The sign preference of hydrogen bonded aqueous ionic clusters X+/-(H(2)O)(i) (n =1-5, X = F; Cl; Br) has been investigated using the Density Functional Theory and ab initio MP2 method. The present study indicates the anomalously large difference in formation free energies between cations and anions of identical chemical composition. The effect of vibrational anharmonicity on stepwise Gibbs free energy changes has been investigated, and possible uncertainties associated with the harmonic treatment of vibrational spectra have been discussed.

Keywords: DFT; Gibbs free energies; Ionic clusters; ab initio; hydrogen bonded complexes; sign preference.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Chemical Phenomena*
Hydrogen / chemistry
Ions / chemistry
Thermodynamics*
Water / chemistry

Substances

Ions
Water
Hydrogen