A remarkably simple dispersion damping scheme and the DH24 double hybrid density functional

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Materials Science

Background:

• Recent advancements introduced the DH23 double hybrid density functional, based on local physics and trained on the GMTKN55 database.
• The DH23 functional achieved a record low WTMAD2 error of 1.73 kcal/mol for the revDH23 variant on the GMTKN55 dataset.

Purpose of the Study:

• To simplify the DH23 double hybrid density functional.
• To develop a new functional, DH24, with a simplified dispersion damping scheme.

Main Methods:

• Introduced a new dispersion damping scheme for DH23.
• The scheme utilizes only atomic numbers and a single global parameter.
• The new functional, DH24, was developed and evaluated.

Main Results:

• The simplified DH24 functional demonstrates performance comparable to its predecessors.
• DH24 maintains the high accuracy achieved by DH23 on the GMTKN55 database.
• The WTMAD2 error for DH24 is expected to be competitive with state-of-the-art double hybrid functionals.

Conclusions:

• The simplified DH24 functional offers a more computationally efficient approach to electronic structure calculations.
• DH24 provides a balance between accuracy and simplicity for predicting chemical properties.
• This work contributes to the development of more practical and accurate computational chemistry tools.