Density functional benchmark for quadruple hydrogen bonds | JoVE Visualize

Area of Science:

Computational Chemistry
Quantum Chemistry
Supramolecular Chemistry

Background:

Hydrogen bonding is a key non-covalent interaction crucial for molecular self-organization and supramolecular structures.
Accurate description of hydrogen bonding via *ab initio* methods is computationally expensive for large systems.
Density functional theory (DFT) provides a balance of accuracy and computational efficiency for large molecular assemblies.

Purpose of the Study:

To benchmark the performance of 152 density functional approximations (DFAs) in reproducing highly accurate hydrogen bonding energies.
To identify the most reliable DFAs for studying hydrogen bonding in large molecular systems.
To guide the selection of appropriate DFAs for computational chemistry applications involving hydrogen bonds.

Main Methods:

Utilized a dataset of highly accurate hydrogen bonding energies for 14 quadruply hydrogen-bonded dimers, previously obtained by extrapolating coupled-cluster energies to the complete basis set limit.
Evaluated 152 different DFAs for their ability to reproduce these benchmark hydrogen bonding energies.
Analyzed the performance of various functional families, including Berkeley and Minnesota functionals, with and without dispersion corrections.

Main Results:

The B97M-V functional, when combined with the D3BJ dispersion correction, emerged as the top-performing DFA.
Eight variants of Berkeley functionals and two Minnesota 2011 functionals (with dispersion corrections) were among the ten best-performing DFAs.
Modifications to the dispersion components of other Berkeley functionals resulted in decreased accuracy.

Conclusions:

The B97M-V functional with D3BJ dispersion correction is recommended as the best DFA for accurately calculating hydrogen bonding energies.
The study highlights the importance of dispersion corrections and specific functional designs for reliable DFT calculations of hydrogen bonds.
Findings provide essential guidance for researchers selecting DFT methods for studying hydrogen bonding in complex systems.