CHAL336 Benchmark Set: How Well Do Quantum-Chemical Methods Describe Chalcogen-Bonding Interactions?

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Chemical Physics

Background:

• Chalcogen bonding (CB) is a significant noncovalent interaction.
• Accurate computational methods are crucial for understanding CB interactions.
• Existing benchmark sets may not comprehensively cover diverse CB scenarios.

Purpose of the Study:

• To introduce the CHAL336 benchmark set, the most extensive database for evaluating chalcogen-bonding interactions.
• To assess the performance of various density functional theory (DFT) methods for CB interactions.
• To provide guidance on selecting accurate computational protocols for CB studies.

Main Methods:

• Development of the CHAL336 benchmark set comprising 336 dimers with diverse CB types (e.g., chalcogen-chalcogen, chalcogen-π).
• High-level reference calculations using established accurate methods.
• Systematic evaluation of 109 dispersion-corrected and dispersion-uncorrected DFT methods.

Main Results:

• Double-hybrid DFT functionals demonstrate superior accuracy for CB interactions.
• Specific double-hybrid functionals (SOS0-PBE0-2-D3(BJ), revDSD-PBEP86-D3(BJ), B2NCPLYP-D3(BJ)) are identified as the most reliable.
• Popular methods like B3LYP and MP2 are found to be less reliable for CB interactions.
• Density-driven errors significantly impact the accuracy of some DFT methods.

Conclusions:

• Double-hybrid DFT methods are the recommended choice for accurate calculations of chalcogen-bonding interactions.
• The CHAL336 benchmark set serves as a valuable resource for future method development and validation.
• A shift towards more robust and accurate computational protocols for CB interactions is encouraged.