Best practices in `0 K' DFT energy calculations on molecular crystal structures

Area of Science:

• Computational Chemistry
• Materials Science
• Solid-State Physics

Background:

• Accurate energy calculations for molecular crystals are crucial in various scientific disciplines.
• Non-experts often require clear guidelines for performing or evaluating these calculations.
• Existing methods may lack sufficient detail for reproducible and reliable results.

Purpose of the Study:

• To provide best practices for performing zero Kelvin energy calculations on molecular crystals.
• To guide non-experts in conducting their own calculations or assessing literature data.
• To enhance the accuracy and validity of computational studies on molecular crystals.

Main Methods:

• Energy optimization of crystal structures using dispersion-corrected density functionals (e.g., PBE+D).
• Assessment of geometric distortions post-minimization to determine the need for further calculations.
• Application of single-point energy calculations with hybrid functionals (e.g., PBE0) and dispersion corrections when necessary.
• Consideration of higher-level theory methods (e.g., MP2D, ωB97X+D) for individual molecules to address conformations and tautomers.

Main Results:

• A step-by-step computational procedure is outlined for molecular crystal energy calculations.
• Criteria are established for deciding the necessity and meaningfulness of subsequent computational steps.
• The workflow allows for progressive refinement of energy calculations based on initial results.

Conclusions:

• The recommended procedure offers a robust framework for accurate zero Kelvin energy calculations on molecular crystals.
• Following these best practices can improve the reliability of computational results in scientific literature.
• This guide empowers researchers, including non-experts, to perform and interpret crystal energy calculations effectively.