title: Assessing DFT-D3 Damping Functions Across Widely Used Density Functionals: Can We Do Better?
abstract: With the aim of improving the utility of the DFT-D3 empirical dispersion correction, we herein generalize the DFT-D3 damping function by optimizing an additional parameter, an exponent, which controls the rate at which the dispersion tail is activated. This method - DFT-D3(op), shorthand for "optimized power," where power refers to the newly introduced exponent - is then parametrized for use with ten popular density functional approximations across a small set of noncovalent interactions and isomerization energies; the resulting methods are then evaluated across a large independent test set of 2475 noncovalent binding energies and isomerization energies. We find that the DFT-D3(op) tail represents a substantial improvement over existing damping functions, as it affords significant reductions in errors associated with noncovalent interaction energies and geometries. The revPBE0-D3(op) and MS2-D3(op) methods in particular stand out, and our extensive testing indicates they are competitive with other modern density functionals.
authors.forename: Jonathon
authors.identifier: http://orcid.org/0000-0002-7016-7346
authors.initials: J
authors.lastname: Witte
authors.forename: Narbe
authors.initials: N
authors.lastname: Mardirossian
authors.affiliation: Kavli Energy Nanosciences Institute at Berkeley, Berkeley, California 94720, United States.
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Neaton
authors.forename: Martin
authors.identifier: http://orcid.org/0000-0002-4309-6669
authors.initials: M
authors.lastname: Head-Gordon