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Journal of Chemical Physics / Volume 135 / Issue 24 / ARTICLES / Theoretical Methods and Algorithms

J. Chem. Phys. 135, 244106 (2011); http://dx.doi.org/10.1063/1.3671384 (8 pages)

Rigorous formulation of two-parameter double-hybrid density-functionals

Emmanuel Fromager

Laboratoire de Chimie Quantique, Institut de Chimie, CNRS/Université de Strasbourg, 4 rue Blaise Pascal, 67000 Strasbourg, France

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(Received 7 September 2011; accepted 1 December 2011; published online 28 December 2011)

A two-parameter extension of the density-scaled double hybrid approach of Sharkas et al. [J. Chem. Phys. 134, 064113 (2011)] is presented. It is based on the explicit treatment of a fraction of multideterminantal exact exchange. The connection with conventional double hybrids is made when neglecting density scaling in the correlation functional as well as second-order corrections to the density. In this context, the fraction ac of second-order Møller-Plesset (MP2) correlation energy is not necessarily equal to the square of the fraction ax of Hartree-Fock exchange. More specifically, it is shown that ac ≤ ax2, a condition that conventional semi-empirical double hybrids actually fulfill. In addition, a new procedure for calculating the orbitals, which has a better justification than the one routinely used, is proposed. Referred to as λ1 variant, the corresponding double hybrid approximation has been tested on a small set consisting of H2, N2, Be2, Mg2, and Ar2. Three conventional double hybrids (B2-PLYP, B2GP-PLYP, and PBE0-DH) have been considered. Potential curves obtained with λ1- and regular double hybrids can, in some cases, differ significantly. In particular, for the weakly bound dimers, the λ1 variants bind systematically more than the regular ones, which is an improvement in many but not all cases. Including density scaling in the correlation functionals may of course change the results significantly. Moreover, optimized effective potentials based on a partially-interacting system could also be used to generate proper orbitals. Work is currently in progress in those directions.

© 2011 American Institute of Physics

Article Outline

  1. INTRODUCTION
  2. THEORY
    1. Multideterminantal exact exchange
    2. Density-scaled two-parameter single hybrids
    3. Density-scaled two-parameter double hybrids
    4. Connection with conventional double hybrids
    5. Summary
  3. COMPUTATIONAL DETAILS
  4. RESULTS AND DISCUSSION
  5. CONCLUSIONS

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KEYWORDS and PACS

Keywords

argon, beryllium, density functional theory, HF calculations, hydrogen neutral molecules, magnesium, nitrogen, perturbation theory, potential energy surfaces

PACS

ARTICLE DATA

Digital Object Identifier
http://dx.doi.org/10.1063/1.3671384

PUBLICATION DATA

ISSN

0021-9606 (print)  
1089-7690 (online)

Publisher

$abstract.society.value is a Member of CrossRef American Institute of Physics

For access to fully linked references, you need to log in.
    K. Sharkas, J. Toulouse, and A. Savin, J. Chem. Phys. 134, 064113 (2011)JCPSA6000134000006064113000001.

    E. Brémond and C. Adamo, J. Chem. Phys. 135, 024106 (2011)JCPSA6000135000002024106000001.

    S. Paziani, S. Moroni, P. Gori-Giorgi, and G. B. Bachelet, Phys. Rev. B 73, 155111 (2006).

    M. Levy and J. P. Perdew, Phys. Rev. B 48, 11638 (1993).

    E. Fromager and H. J. Aa. Jensen, Phys. Rev. A 78, 022504 (2008).

    P. Mori-Sanchez, Q. Wu, and W. Yang, J. Chem. Phys. 123, 062204 (2005)JCPSA6000123000006062204000001.

    J. Toulouse, K. Sharkas, E. Brémond, and C. Adamo, J. Chem. Phys. 135, 101102 (2011)JCPSA6000135000010101102000001.

    J. P. Perdew, K. Burke, and M. Ernzerhof, Phys. Rev. Lett. 77 (1996).

    J. P. Perdew, J. A. Chevary, S. H. Vosko, K. A. Jackson, M. R. Pederson, D. J. Singh, and C. Fiolhais, Phys. Rev. B 46, 6671 (1992).

    G. C. Lie and E. Clementi, J. Chem. Phys. 60, 1288 (1974)JCPSA6000060000004001288000001.

    J. C. Sancho-García and A. J. Pérez-Jiménez, J. Chem. Phys. 131, 084108 (2009)JCPSA6000131000008084108000001.


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