Volume 4 Supplement 1

7th German Conference on Chemoinformatics: 25 CIC-Workshop

Open Access

Applying the unified pH scale: absolute acidities in the gas phase and anchor points for eleven representative liquid media

Journal of Cheminformatics20124(Suppl 1):P8

DOI: 10.1186/1758-2946-4-S1-P8

Published: 1 May 2012

The investigations on our recently introduced unified acidity scale [1] based on the absolute chemical potential of the proton pointed out the inadequateness of the established GA scale. Earlier it was inter alia found that, when trying to correlate pKa with GA values, in several cases the correlation was broken without any sufficient explanation [2, 3]. However, the GA does not take into account the pressure dependent speciation in the gas phase. In this contribution we systematically extend the theory of acidity in the gas phase from standard GAs and GBs to the real existing bulk phases [4].

Furthermore we present the rCCC (relaxed COSMO cluster-continuum) model [5], a quantum chemical solvation model for the calculation of Gibbs solvation energies of the proton with good accuracy. The rCCC values can be used to anchor individual pH scales in different solvents to our universal scale.

Authors’ Affiliations

(1)
Institute for Inorganic and Analytical Chemistry, Freiburger Materialforschungszentrum FMF and Freiburg Institute for Advanced Studies (FRIAS), Albert-Ludwigs-Universität Freiburg
(2)
Institute of Chemistry, University of Tartu

References

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  3. Kütt A, Leito I, Kaljurand I, Sooväli L, Vlasov VM, Yagupolskii LM, Koppel IA: A comprehensive self-consistent spectrophotometric acidity scale of neutral Brønsted acids in acetonitrile. J Org Chem. 2006, 71: 2829-2838. 10.1021/jo060031y.View ArticleGoogle Scholar
  4. Himmel D, Goll SK, Leito I, Krossing I: . to be published
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Copyright

© Goll et al; licensee BioMed Central Ltd. 2012

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.