Teale, Andrew M. and Helgaker, Trygve and Savin, Andreas (2015) Alternative representations of the correlation energy in density-functional theory: a kinetic-
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چکیده
The adiabatic-connection framework has been widely used to explore the properties of the correlation energy in density-functional theory. The integrand in this formula may be expressed in terms of the electron–electron interactions directly, involving intrinsically two-particle expectation values. Alternatively, it may be expressed in terms of the kinetic energy, involving only one-particle quantities. In this work, we explore this alternative representation for the correlation energy and highlight some of its potential for the construction of new density functional approximations. The kineticenergy based integrand is effective in concentrating static correlation effects to the low interaction strength regime and approaches zero asymptotically, offering interesting new possibilities for modelling the correlation energy in density-functional theory.
منابع مشابه
Rebolini, Elisa and Toulouse, Julien and Teale, Andrew M. and Helgaker, Trygve and Savin, Andreas (2015) Excited states from range-separated density-functional perturbation
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Elisa Rebolini,1,2,4,* Julien Toulouse,1,2,† Andrew M. Teale,3,4,‡ Trygve Helgaker,4,§ and Andreas Savin1,2,∥ 1Sorbonne Universités, UPMC Université Paris 06, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris, France 2CNRS, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris, France 3School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom 4...
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