Accession Number : ADA269236

Title :   Scales of Hydrogen Bonding Workshop Held in London, England on July 1-3, 1987.

Descriptive Note : Final rept.,

Corporate Author : SURREY UNIV GUILDFORD (UNITED KINGDOM) DEPT OF CHEMISTRY

Personal Author(s) : Abraham, Michael H.

Report Date : JUL 1987

Pagination or Media Count : 52

Abstract : About 25 chemists took part in the ONRL-sponsored workshop, 'Scales of Hydrogen-bonding,' held in London from 1 through 3 July 1987. The purpose of the gathering was to discuss current activities in setting up scales of both solute and solvent hydrogen-bond strength. The importance of solute hydrogen-bond scales in the understanding and prediction of effects in such diverse areas as solubilities in water and in blood, water-solvent partition coefficients, toxicological studies, and the response of chemical microsensor coatings to vapors. Work on scales of solute hydrogen-bond acidity and basicity is well advanced. Most of these scales are based on log K values for hydrogen-bond complexation in dilute solution - that is, they are nearly always Gibbs energy related scales. Theoretical work by I. H. Hillier (University of Manchester, UK) has demonstrated that such scales are likely to be more easily handled than scales based on enthalpies of complexation. Not so much work is ongoing in the area of solvent scales, and what work there is seems to be exclusively oriented to solvent hydrogen-bond basicity. P.-C. Maria and J.-F. Gal (University of Nice, France) described their multivariate analysis that leads to an angle Theta, descriptive of the electrostatic: covalent ratio in the base:reference acid complex. M.H. Abraham (University of Surrey, UK) showed that it was possible to demonstrate the virtual equivalence of a solute scale and a solvent scale of hydrogen-bond basicity for nonassociated compounds, provided that the reference acids in each case led to Theta values that were almost the same - around 65 deg.... Hydrogen bonding, Solvent basicity scales.

Descriptors :   *HYDROGEN BONDS, *SOLUTES, *SOLVENTS, *SOLUBILITY, ACIDS, ANGLES, BLOOD, CHEMICALS, COATINGS, COEFFICIENTS, ELECTROSTATICS, ENERGY, MULTIVARIATE ANALYSIS, PREDICTIONS, RATIOS, RESPONSE, VAPORS, WATER, WORKSHOPS, TOXICOLOGY, DETECTORS, BASES(CHEMISTRY), DILUTION, ENTHALPY, COVALENT BONDS, COMPLEX COMPOUNDS, CORRELATION, PARAMETERS, REGRESSION ANALYSIS.

Subject Categories : Physical Chemistry
      Thermodynamics
      Statistics and Probability

Distribution Statement : APPROVED FOR PUBLIC RELEASE