Accurate prediction of the enthalpies of formation for xanthophylls
| Autor: | Ching-Han Hu, Fu-Xing Liao, Jenn-Huei Lii |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
chemistry.chemical_classification
Training set General Chemistry Xanthophylls Carotenoids Standard enthalpy of formation Absolute deviation Computational Mathematics Models Chemical chemistry Artificial Intelligence Consistency (statistics) Xanthophyll Thermodynamics Molecule Physical chemistry Density functional theory |
| Zdroj: | Journal of Computational Chemistry. 32:3175-3187 |
| ISSN: | 0192-8651 |
| DOI: | 10.1002/jcc.21899 |
| Popis: | This study investigates the applications of computational approaches in the prediction of enthalpies of formation (ΔHf) for C-, H-, and O-containing compounds. Molecular mechanics (MM4) molecular mechanics method, density functional theory (DFT) combined with the atomic equivalent (AE) and group equivalent (GE) schemes, and DFT-based correlation corrected atomization (CCAZ) were used. We emphasized on the application to xanthophylls, C-, H-, and O-containing carotenoids which consist of ∼ 100 atoms and extended π-delocaization systems. Within the training set, MM4 predictions are more accurate than those obtained using AE and GE; however a systematic underestimation was observed in the extended systems. ΔHf for the training set molecules predicted by CCAZ combined with DFT are in very good agreement with the G3 results. The average absolute deviations (AADs) of CCAZ combined with B3LYP and MPWB1K are 0.38 and 0.53 kcal/mol compared with the G3 data, and are 0.74 and 0.69 kcal/mol compared with the available experimental data, respectively. Consistency of the CCAZ approach for the selected xanthophylls is revealed by the AAD of 2.68 kcal/mol between B3LYP-CCAZ and MPWB1K-CCAZ. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011 |
| Databáze: | OpenAIRE |
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