Publication: Gas phase carbon acidity and correlations with aqueous pKa values: A comparison of B3LYP/6-311++G(d,p), Gaussian-4 (G4), and experimental approaches
All || By Area || By Year| Title | Gas phase carbon acidity and correlations with aqueous pKa values: A comparison of B3LYP/6-311++G(d,p), Gaussian-4 (G4), and experimental approaches | Authors/Editors* | S Rayne, K Forest |
|---|---|
| Where published* | Nature Precedings |
| How published* | Other |
| Year* | 2010 |
| Volume | |
| Number | |
| Pages | http://dx.doi.org/10.1038/npre.2010.4381.1 |
| Publisher | Nature Publishing Group |
| Keywords | carbon acids; aqueous pKa; gas phase acidity; theoretical study; quantitative structure-property relationship; density functional theory; G4 composite method |
| Link | |
| Abstract |
Gas phase standard state (298.15 K, 1 atm) calculations were conducted at the B3LYP/6-311++G(d,p) density functional and the Gaussian-4 (G4) composite method levels of theory to estimate the acidity of various carbon acids. Excellent agreement was found between the G4 gas phase enthalpies and free energies of carbon acid dissociation and corresponding experimental values. The B3LYP/6-311++G(d,p) level of theory displayed a significantly lower accuracy for gas phase acidity prediction, but with similar qualitative trends as the G4 calculations. Good correlations using both theoretical methods were found with corresponding carbon acid aqueous pKa values. However, the pKa prediction accuracy of carbon acids based on correlations with theoretical gas phase acidities appears lower than previously reported. Some carbon acid moieties may be outliers in general aqueous pKa versus gas phase acidity quantitative structure-property relationships (QSPRs), warranting further investigative efforts on broader training sets. |
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