Correlation between empirical solvent polarity scales and computed quantities derived from molecular surface electrostatic potentials

摘要

Analysis of five empirical solvent polarity scales E_T~N, #pi#~*, Py, S' and SPP is carried out by correlating them with and #sigma#~(2-tot), two computed quantities derived from molecular surface elctrostatic potentials. Our results indicate (i) that the S' scale should be a good global solvent polarity scale, (ii) that it would be inappropriate to use the E_(T~N) and Py scales to describe non-specific solute-solvent interactions for protic solvents, and (iii) that the #pi#~* and SPP scales are probably contaminated with caarge-transfer effects for aromatic and polychlorinated solvents. The differences between our results and those obtained by the correlation of empirical scales with a theoretical thermodynamic analysis result (E_PNA) are discussed in the context of intermolecular interactions between the probe solutes and the solvent considered.