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Efficient, direct self-consistent-field method in density-functional theory
Physical Review A, 1996We have developed a direct self-consistent-field (SCF) molecular-orbital (MO) method based on the density-functional linear combinations of atomic-orbital methods, which is efficient for obtaining total energies of large molecules. In this method, we introduce the Schwartz inequality and efficiently reduce the number of atomic-orbital pairs, which must
, Kobayashi, , Tago, , Kurita
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Direct Method for Optimized Effective Potentials in Density-Functional Theory
Physical Review Letters, 2002The conventional optimized effective potential method is based on a difficult-to-solve integral equation. In the new method, this potential is constructed as a sum of a fixed potential and a linear combination of basis functions. The energy derivatives with respect to the coefficients of the linear combination are obtained. This enables calculations by
Weitao, Yang, Qin, Wu
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Car-Parrinello treatment for an approximate density-functional theory method
The Journal of Chemical Physics, 2007The authors formulate a Car-Parrinello treatment for the density-functional-based tight-binding method with and without self-consistent charge corrections. This method avoids the numerical solution of the secular equations, the principal drawback for large systems if the linear combination of atomic orbital ansatz is used.
Mathias, Rapacioli +3 more
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Overview of Density Functional Theory and Methods
1994Condensed matter physics and materials science are concerned fundamentally with understanding and exploiting the properties of systems of interacting electrons and atomic nuclei. This has been well known since the development of quantum mechanics. With this comes the recognition that, at least in principal, almost all properties of materials can be ...
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Advanced Density Functional Theory Methods tor Materials Science
2014In this work we chiefly deal with two broad classes of problems in computational materials science, determining the doping mechanism in a semiconductor and developing an extreme condition equation of state. While solving certain aspects of these questions is well-trodden ground, both require extending the reach of existing methods to fully answer them.
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Novel Electron Correlation Methods: Multiconfigurational Density Functional Theory.
1997Abstract : The multiconfigurational density functional theory (MCDFT) software Schrodinger, Inc. has developed in Phase I of this project combines many of the advantages of generalized valence bond (GVB) and restricted configuration interaction (RCI) techniques with those of DFT.
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Electronic Structure Methods Based on Density Functional Theory
2009Abstract Electronic structure methods based on the density functional theory (DFT) are used as a powerful tool for assessing the mechanical thermodynamic and defect properties of metal alloys. This article presents the origins of the electronic structure methods and their strengths and limitations.
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Geminal functional theory: A synthesis of density and density matrix methods
The Journal of Chemical Physics, 2000The energy of any atom or molecule with an even number N of electrons is shown to be an exact functional of a single geminal where the functionals for both the kinetic energy and the external potential are explicitly known. We derive the foundations for geminal functional theory (GFT) through a generalized constrained search and the use of two theorems
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Hybrid methods: Combining density functional and wavefunction theory
2008Hybrid methods of density-functional and wavefunction theory have proven to be powerful tools in electronic structure theory. The Kohn-Sham scheme is already a hybrid scheme, since part of the kinetic energy of the system is calculated from the Kohn-Sham wavefunction.
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Multigrid methods in density functional theory
International Journal of Quantum Chemistry, 1997Thomas L. Beck +2 more
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