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Updated: Sep 30, 2025
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Optimization of Synthetic Proteins: Identification of Interpositional Dependencies Indicating Structurally and/or Functionally Linked Residues
Published on: July 14, 2015
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The interplay of intra- and intermolecular errors in modeling conformational polymorphs.
Gregory J O Beran1, Sarah E Wright2, Chandler Greenwell1
1Department of Chemistry, University of California, Riverside, California 92521, USA.
The Journal of Chemical Physics
|March 16, 2022
Summary
Quantum chemistry models struggle with organic crystal polymorphs due to complex interactions. Some density functionals show significant errors, relying on error cancellation for accurate predictions of crystal energies.
Area of Science:
- Computational Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Conformational polymorphism in organic crystals presents significant challenges for quantum chemistry.
- Accurate modeling requires precise balancing of intra- and intermolecular forces.
Purpose of the Study:
- To evaluate various van der Waals-inclusive quantum chemistry methods for predicting conformational polymorph energies.
- To investigate the impact of delocalization error on monomer and crystal properties.
- To establish benchmark datasets for testing computational models.
Main Methods:
- Analysis of 54 molecular conformations from 20 conformational polymorph sets.
- Calculation of relative lattice energies and dimer interactions.
- Application of density functional theory (DFT) models, SCS-MP2D, and DLPNO-CCSD(T).
Main Results:
- Several DFT functionals (e.g., B86bPBE-XDM, PBE-D4) exhibit notable errors, with crystal energy prediction accuracy depending on error cancellation.
- SCS-MP2D and ωB97M-V models show reduced errors and less reliance on error cancellation.
- Established CP1b and CP2b benchmark datasets from DLPNO-CCSD(T) calculations.
Conclusions:
- The accuracy of DFT methods for conformational polymorphs is sensitive to delocalization errors and error cancellation.
- SCS-MP2D offers a more reliable approach for these systems.
- The new benchmark datasets will aid in developing and validating quantum chemistry models for complex molecular systems.
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