Results 231 to 240 of about 241,907 (265)

Embedding wave function theory in density functional theory

The Journal of Chemical Physics, 2006
We present a framework for embedding a highly accurate coupled-cluster calculation within a larger density functional calculation. We use a perturbative buffer to help insulate the coupled-cluster region from the rest of the system. Regions are defined, not in real space, but in Hilbert space, though connection between the two can be made by spatial ...
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The density in density functional theory

Journal of Molecular Structure: THEOCHEM, 2010
Abstract The paper begins with the definition of the electron density given by Schrodinger in 1926 and traces its use and many applications directed at the understanding of the properties of matter to its present day role in density functional theory and the development of the quantum mechanics of an open system.
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Density functional theory

2001
Classical phenomenological description of nucleation is based on the capillarity approximation treating all droplets (clusters) as if they were macroscopic objects characterized by a well defined rigid boundary of radius \(R\) with a bulk liquid density inside \(R\) and bulk vapor density outside \(R\).
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A conundrum for density functional theory

Science, 2017
DFT studies may sometimes get the right results for the wrong ...
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Relativistic density functional theory

2005
In these lectures on relativistic density functional theory I had the choice to provide a kind of survey, or to concentrate on a few specific aspects in greater detail. I chose the first option. In order to give you the opportunity to fill in the (often gory) details, I will distribute a list of references, augmented by suitable comments on the ...
Eberhard Engel, Reiner M. Dreizler
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TIME-DEPENDENT DENSITY FUNCTIONAL THEORY

Annual Review of Physical Chemistry, 2003
▪ Abstract  Time-dependent density functional theory (TDDFT) can be viewed as an exact reformulation of time-dependent quantum mechanics, where the fundamental variable is no longer the many-body wave function but the density. This time-dependent density is determined by solving an auxiliary set of noninteracting Schrödinger equations, the Kohn-Sham ...
M A L, Marques, E K U, Gross
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Overview of Density Functional Theory

1995
In these lectures I will first offer some “warm-up exercises” for density functional theory (DFT), to help prepare the ground for the many interesting papers which will follow. After that I will present some very recent work which promises to allow density functional calculations for systems of very many (103 − 105) atoms.
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Symmetry in density-functional theory

Physical Review A, 1993
The formal structure of density-functional theory in the constrained-search formulation is analyzed and a theory is derived which is symmetrized with respect to the symmetry group of the Hamiltonian operator. This theory is valid for an arbitrary given electronic system and takes into account symmetries in spin as well as in ordinary space.
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Corollary to density-functional theory

Physical Review A, 1990
It is shown that the exact total-energy eigenvalue of the Schrodinger equation is a functional of the Hartree-Fock charge density. Furthermore, the exact correlation energy, defined as the correction to the Hartree-Fock energy, is a universal functional of the Hartree-Fock charge density.
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Density-Functional Theory of the Band Gap

Physical Review B, 1985
Publisher Summary This chapter discusses the density-functional theory (DFT) of the band gap. Emphasizing the dependence of the density functionals on the number of particles brings out the difference between the highest occupied energy of the (N +1)-particle system and the (N + 1) th level of the N-particle system.
, Sham, , Schlüter
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