Range-separated double-hybrid density-functional theory with coupled-cluster and random-phase approximations

Abstract

We construct range-separated double-hybrid schemes which combine coupled-cluster or random-phase approximations with a density functional based on a two-parameter Coulomb-attenuating-method-like decomposition of the electron-electron interaction. We find that the addition of a fraction of short-range electron-electron interaction in the wave-function part of the calculation is globally beneficial for the range-separated doublehybrid scheme involving a variant of the random-phase approximation with exchange terms. Even though the latter scheme is globally as accurate as the corresponding scheme employing only second-order Møller-Plesset perturbation theory for atomization energies, reaction barrier heights, and weak intermolecular interactions of small molecules, it is more accurate for the more complicated case of the benzene dimer in the stacked configuration. The present range-separated double-hybrid scheme employing a random-phase approximation thus represents a new member in the family of double hybrids with minimal empiricism which could be useful for general chemical applications.

Range‐separated multiconfigurational density functional theory methods

“…From the ab initio perspective, RSHs combining DFT either with long-range RPA or long-range MP2 correlation have been intensively developed due to their beneficial cost/accuracy ratio. Recent works have generalized this class of methods to a range-separated double-hybrid scheme [179][180][181] of an improved performance for thermochemistry and noncovalent interactions. RS MC-DFT may also compete with multireference ab initio methods corrected for the dynamic correlation.…”

Short‐range correlation energy of the relativistic homogeneous electron gas

“…Range-separated density-functional theory (RS-DFT) (see, e.g., References [1,2]) is an extension of Kohn-Sham density-functional theory (KS-DFT) [3] which allows one to rigorously combine a multideterminant wave-function method accounting for the long-range part of the electron-electron interaction with a complementary short-range density functional. RS-DFT can improve over usual Kohn-Sham densityfunctional approximations for the electronic-structure calculations of strongly correlated systems (see, e.g., References [4,5]) and/or systems involving weak intermolecular interactions (see, e.g., References [6,7]), while still enjoying a fast basis convergence [8].…”

Computation of covalent and noncovalent structural parameters at low computational cost: Efficiency of the DH‐SVPD method

“…[ 11–13 ] Others are based on the range‐separation exchange (RSX) scheme [ 14 ] to (partially) cure the self‐interaction and delocalization errors [ 15 ] (SIE and DE, respectively). [ 16–19 ] However, all of them conserve similar features, that is, a fraction of EXX generally larger than 50% and a fraction of PT2 correlation ranging between 10% and 40%, which allow them to reach the chemical accuracy when modeling a large panel of properties ranging from ground‐state energies [ 20 ] to structures [ 21,22 ] and extending to singlet‐singlet vertical excitation energies. [ 23,24 ]…”