ChemRxiv
These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
BenzeneDimers-Manuscript.pdf (2.02 MB)
0/0

Are Dispersion Corrections Accurate Outside Equilibrium? A Case Study on Benzene

preprint
submitted on 22.02.2018 and posted on 23.02.2018 by Tim Gould, Erin R. Johnson, Sherif Abdulkader Tawfik
Modern approaches to modelling dispersion forces are becoming increasingly accurate, and can predict accurate binding distances and energies. However, it is possible that these successes reflect a fortuitous cancellation of errors at equilibrium. Thus, in this work we investigate whether a selection of modern dispersion methods agree with benchmark calculations across several potential-energy curves of the benzene dimer to determine if they are capable of describing forces and energies outside equilibrium. We find the exchange-hold dipole moment (XDM) model describes most cases with the highest overall agreement with reference data for energies and forces, with many-body dispersion (MBD) and its fractionally ionic (FI) variant performing essentially as well. Popular approaches, such as Grimme-D and van der Waals density functional approximations (vdW-DFAs) underperform on our tests. The meta-GGA M06-L is surprisingly good for a method without explicit dispersion corrections. Some problems with SCAN+rVV10 are uncovered and briefly discussed.

Funding

ARC DP160101301

History

Email Address of Submitting Author

t.gould@griffith.edu.au

Email Address(es) for Other Author(s)

erin.johnson@dal.ca, Sherif.Abbas@uts.edu.au

Institution

Griffith University

Country

Australia

ORCID For Submitting Author

0000-0002-7191-9124

Declaration of Conflict of Interest

no conflict of interest

Exports

Read the published paper

in Beilstein Journal of Organic Chemistry

Logo branding

Exports