Alternative separation of exchange and correlation energies in range-separated density-functional perturbation theory

Abstract

An alternative separation of short-range exchange and correlation energies is used in the framework of second-order range-separated density-functional perturbation theory. This alternative separation was initially proposed by Toulouse et al. [Theor. Chem. Acc. 114, 305 (2005)] and relies on a long-range interacting wavefunction instead of the non-interacting Kohn-Sham one. When second-order corrections to the density are neglected, the energy expression reduces to a range-separated double-hybrid (RSDH) type of functional, RSDHf, where "f" stands for "full-range integrals" as the regular full-range interaction appears explicitly in the energy expression when expanded in perturbation theory. In contrast to usual RSDH functionals, RSDHf describes the coupling between long- and short-range correlations as an orbital-dependent contribution. Calculations on the first four noble-gas dimers show that this coupling has a significant effect on the potential energy curves in the equilibrium region, improving the accuracy of binding energies and equilibrium bond distances when second-order perturbation theory is appropriate.

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References in corpus (5)

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• Double-hybrid density-functional theory made rigorous
• Long-range-corrected hybrids including RPA correlation
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Cited by in corpus (10)

• Assessing the Tamm-Dancoff Approximation, singlet-singlet, and singlet-triplet excitations with the latest long-range corrected double-hybrid density functionals
• A general range-separated double-hybrid density-functional theory
• Range-separated multideterminant density-functional theory with a short-range correlation functional of the on-top pair density
• Basis convergence of range-separated density-functional theory
• Alternative separation of exchange and correlation energies in multi-configuration range-separated density-functional theory
• Double hybrid density-functional theory using the Coulomb-attenuating method
• Excitation energies along a range-separated adiabatic connection
• Ghost interaction correction in ensemble density-functional theory for excited states with and without range separation
• Combining Density Functional Theory and Green's Function Theory: Range-Separated, Non-local, Dynamic, and Orbital-Dependent Hybrid Functional
• Excitation energies from G{ö}rling-Levy perturbation theory along the range-separated adiabatic connection