Document type
Journal articles
Document subtype
Full paper
Title
The separation between solvent polarizability and solvent dipolarity: Revisiting the Kamlet-Abraham-Taft model equation
Participants in the publication
Luís Moreira (Author)
Ruben Elvas-Leitão (Author)
Filomena Martins (Author)
Dep. Química e Bioquímica
CQE
Summary
Quantitative structure–property relationships were established using multiple linear regressions to correlate log k values for the heterolysis reaction of 3-bromo-3-ethylpentane using three well-known model equations, the Kamlet-Abraham-Taft (KAT), the Catalán (Cat) and the Laurence (Lau) equations. The a priori exclusion of the hydrogen bond acceptor (HBA) basicity descriptor for all tested models led to similar responses, thus emptying the argument of an alleged use of a non-balanced set of solvents. Concurrently, a new method was devised to split the original Kamlet-Taft π* descriptor into two independent contributions which separately quantify the solvent’s polarizability (DI) and dipolarity (Dip). A modified version of the KAT equation (mKAT) including both DI and Dip, together with the exclusion of the HBA basicity descriptor was applied to five selected solvent-dependent physicochemical processes. Results showed that the mKAT model provided significant improvements over the original KAT model. Additionally, it was shown that the introduction of DI in the truncated KAT equation could lead to misleading or, at best, inconclusive interpretations of solvent effects. Finally, the performance of mKAT model was compared with Catalán’s and Laurence’s model equations in terms of statistical results, relevance of descriptors and gas-phase predictions. In general, these three model equations show very similar outcomes although the mKAT model exhibits an overall better performance.
Date of Submisson/Request
2022-04-12
Date of Acceptance
2022-06-16
Date of Publication
2022-09
Institution
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Where published
Journal of Molecular Liquids
Publication Identifiers
ISSN - 0167-7322
Publisher
Elsevier BV
Number of pages
8
Starting page
119656
Document Identifiers
DOI -
https://doi.org/10.1016/j.molliq.2022.119656
URL -
http://dx.doi.org/10.1016/j.molliq.2022.119656
Rankings
Web Of Science Q1 (2022) - 6.0 - Physics, Atomic, Molecular & Chemical
Web Of Science Q2 (2022) - 6.0 - Chemistry, Physical
SCIMAGO Q1 (2022) - 0.914 - Physical and Theoretical Chemistry
Keywords
Quantitative structure property relationships Kinetics Solvent effects Solvent polarizability Solvent dipolarity Model equations