CCSD(T), W1, and other model chemistry predictions for gas-phase deprotonation reactions
Publication Date
2006
Description
A series of CCSD(T) single-point calculations on MP4(SDQ) geometries and the W1 model chemistry method have been used to calculate ΔH° and ΔG° values for the deprotonation of 17 gas-phase reactions where the experimental values have reported accuracies within 1 kcal/mol. These values have been compared with previous calculations using the G3 and CBS model chemistries and two DFT methods. The most accurate CCSD(T) method uses the aug-cc-pVQZ basis set. Extrapolation of the aug-cc-pVTZ and aug-cc-pVQZ results yields the most accurate agreement with experiment, with a standard deviation of 0.58 kcal/mol for ΔG° and 0.70 kcal/mol for ΔH°. Standard deviations from experiment for ΔG° and ΔH° for the W1 method are 0.95 and 0.83 kcal/mol, respectively. The G3 and CBS-APNO results are competitive with W1 and are much less expensive. Any of the model chemistry methods or the CCSD(T)/aug-cc-pVQZ method can serve as a valuable check on the accuracy of experimental data reported in the National Institutes of Standards and Technology (NIST) database.
Journal
International Journal of Quantum Chemistry
Volume
106
Issue
15
First Page
3122
Last Page
3128
Department
Chemistry
Link to Published Version
Recommended Citation
Shields, George C.; Pickard, Frank C. IV; Griffith, Daniel R.; Ferrara, Skylar J.; Liptak, Matthew D.; and Kirschner, Karl N.. "CCSD(T), W1, and other model chemistry predictions for gas-phase deprotonation reactions." International Journal of Quantum Chemistry (2006) : 3122-3128.