Double-hybrid density-functional theory made rigorous

Kamal Sharkas; Julien Toulouse; Andreas Savin

doi:10.1063/1.3544215

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arXiv · 1012.5823

Double-hybrid density-functional theory made rigorous

Kamal Sharkas·Julien Toulouse·Andreas Savin

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Abstract

We provide a rigorous derivation of a class of double-hybrid approximations, combining Hartree-Fock exchange and second-order Moller-Plesset correlation with a semilocal exchange-correlation density functional. These double-hybrid approximations contain only one empirical parameter and use a density-scaled correlation energy functional. Neglecting density scaling leads to a one-parameter version of the standard double-hybrid approximations. We assess the performance of these double-hybrid schemes on representative test sets of atomization energies and reaction barrier heights, and we compare to other hybrid approximations, including range-separated hybrids. Our best one-parameter double-hybrid approximation, called 1DH-BLYP, roughly reproduces the two parameters of the standard B2-PLYP or B2GP-PLYP double-hybrid approximations, which shows that these methods are not only empirically close to an optimum for general chemical applications but are also theoretically supported.

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Kamal Sharkas, Julien Toulouse, Andreas Savin. 2011-02-18. Double-hybrid density-functional theory made rigorous. https://doi.org/10.1063/1.3544215

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