Assessment of interaction-strength interpolation formulas for gold and silver clusters

Abstract

The performance of functionals based on the idea of interpolating between the weak- and the strong-interaction limits the global adiabatic-connection integrand is carefully studied for the challenging case of noble-metal clusters. Different interpolation formulas are considered and various features of this approach are analyzed. It is found that these functionals, when used as a correlation correction to Hartree-Fock, are quite robust for the description of atomization energies, while performing less well for ionization potentials. Future directions that can be envisaged from this study and a previous one on main group chemistry are discussed.

Large coupling-strength expansion of the Møller–Plesset adiabatic connection: From paradigmatic cases to variational expressions for the leading terms

“…It has also been found that the Wilson-Levy functional 24 provides a decent generalized gradient approximation (GGA) of E HF c [ρ HF ] for ionization energies 25 and for non-covalent interaction energies. 26,27 More recently, it has been observed that rather accurate interaction energies, 28,29 again especially for non-covalent complexes, 30 can be obtained by modeling the HF correlation energy E HF c with an interpolation between the second-order Møller-Plesset perturbation theory (MP2) and a large coupling-strength limit, which is approximated with the strong-interaction DFT functionals [31][32][33] of the HF density. These interpolations can easily be corrected from their sizeconsistency error 30 and have been shown to also provide a diagnostic indicator for the accuracy of MP2 for non-covalent interactions.…”

MAP: An MP2 Accuracy Predictor for Weak Interactions from Adiabatic Connection Theory

“…This idea was proposed by Seidl and co-workers in the context of the DFT AC. 20,44 Recent papers have also explored its use in the context of the HF AC, obtaining rather good results for interaction energies, particularly 45,46 (but not only 47 ) of non-covalently bonded systems. To use this approach in the HF AC context, we employ the following SPL (after Seidl, Perdew and Levy) interpolation form 44…”

Functional derivative of the zero-point-energy functional from the strong-interaction limit of density-functional theory

“…In Fig. 5 we show the potential in (50) for R = 15. Via (42), δF ZPE /δρ(x) indeed introduces a correction in the mid-bond region.…”