Construction of a parameter-free doubly hybrid density functional from adiabatic connection.
In this work, the adiabatic connection (AC) formalism, coordinate scaling relations, and the second order Görling-Levy perturbation theory (GL2) are first reviewed. Emphasis is laid upon the construction of the AC integrand (Wxc(λ)), with suitable input data {Wxc(0), Wxc'(0), Wxc(1) and the proper asymptotic behavior on λ(-1/2) as λ → ∞. This leads to a non-empirical DH functional, namely, PBE-ACDH. The PBE-ACDH functional is unique in that it explicitly considers contributions from density scaling and singles, and it utilizes density and orbital information from the PBE functional, which has a local multiplicative potential, being most compatible with the GL2 theory. Systematical tests on heats of formation, bond dissociation enthalpies, reaction barrier heights, and nonbonded interactions, using some well-established benchmarking sets, suggest that PBE-ACDH is a significant improvement over its parent functional PBE, as well as PBE0, Becke's Half-and-Half (PBE-HH), and GL2. The physical insight gained in the present work should prove useful for the further development of new functionals.
Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, MOE Laboratory for Computational Physical Science, Department of Chemistry, Fudan University, Shanghai 200433, China.
Neil Qiang
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Su
Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, MOE Laboratory for Computational Physical Science, Department of Chemistry, Fudan University, Shanghai 200433, China.
Xin
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Xu