• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1231-1236
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• 2011

Chiral discrimination is the ability to distinguish one enantiomeric form over another. The differential binding interaction between two molecules with the same helicity and those with the opposite helicity was investigated by using dispersion-corrected density functional theory. [5]helicene, tetrahydro[5]helicene and the polar D-${\pi}$-A compounds, 3,12-dimethoxy-7,8-dicyano-[5]helicene and 3,12-dimethoxy-7,8-dicyano-tetrahydro[5]helicene were the monomers considered in this study. In gas phase, the dimeric interaction from two helical molecules with the opposite handedness is greater than from those with the same handedness. The stable configurations of such dimers were identified. The most stable configuration tends to be the one with maximum contact between monomers.

• 대한화학회지
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• 제63권1호
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• pp.24-28
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• 2019

In this work, we discuss where the failure of Kohn-Sham Density Functional Theory (DFT) occurs in weak interactions. We have adopted density-corrected density functional calculations and dispersion correction separately to find out whether the failure is due to density-driven error or functional error. The results of Benzene Ar complex, one of the most common examples of van der Waals interactions, show that DFT calculations of van der Waals interaction suffer from functional error, rather than density-driven error. In addition, errors in DFT calculations of the S22 dataset, which contains small to relatively large (30 atoms) complexes with non-covalent interactions, are governed by functional errors.

• Coupled systems mechanics
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• 제6권3호
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• pp.369-376
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• 2017

Intermolecular interaction energies and conformer geometries of the hydrogen bonded acrylamide dimers have been studied by using the second-order Møller-Plesset (MP2) perturbation theory and the density functional theory (DFT) with 17 density functionals. Dunning's correlation consistent basis sets (up to aug-cc-pVTZ) have been used to study the basis set effects. The DFT calculated interaction energies are compared to the reference energy data calculated by the MP2 method and the coupled cluster method at the complete basis set (CCSD(T)/CBS) limit in order to determine the relative performance of the studied density functionals. Overall, dispersion-energy-corrected density functionals outperform uncorrected ones. The ${\omega}B97XD$ density functional is particularly effective in terms of both accuracy and computational cost in estimating the reference energy values using small basis sets and is highly recommended for similar calculations for larger systems.