A real-space stochastic density matrix approach for density functional electronic structure

The electronic structure of the perovskite manganites AlMnO3cubic crystal was presented. The calculations were made within density functional theory and PBE exchange correlations energy approximation. It was found that the crystal exhibit covalent bonding between Mn and O with superexchange mechanism. At groundstate, AlMnO3stabilizes in antiferromagnetic structure with semi metallic like nature at the ground state.

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A Real-Space Parallel Optimization Model Reduction Approach for Electronic Structure Computation in Large Nanostructures Using Orbital-Free Density Functional Theory

Applied Mechanics ◽

10.1115/imece2006-15740 ◽

2006 ◽

Author(s):

Dan Negrut ◽

Mihai Anitescu ◽

Anter El-Azab ◽

Steve Benson ◽

Emil Constantinescu ◽

...

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Model Reduction ◽

Density Functional ◽

Energy Functional ◽

Real Space ◽

Parallel Optimization ◽

Functional Theory ◽

Orbital Free ◽

Reduction Approach

The goal of this work is the development of a highly parallel approach to computing the electron density in nanostructures. In the context of orbital-free density functional theory, a model reduction approach leads to a parallel algorithm that mirrors the subdomain partitioning of the problem. The resulting form of the energy functional that is subject to the minimization process is compact and simple. Computation of gradient and hessian information is immediate. The salient attribute of the proposed methodology is the use of model reduction (reconstruction) within the framework of electronic structure computation.

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Electronic structure of the PrNiBi half-Heusler system based on the σGGA + U method

Scientific Reports ◽

10.1038/s41598-019-56537-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

L. Mikaeilzadeh ◽

A. Tavana ◽

F. Khoeini

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

Electronic Structure ◽

Band Structure ◽

Ground State ◽

Density Functional ◽

Functional Theory ◽

Band Inversion ◽

Topological State ◽

Antiferromagnetic Ground State

AbstractIn this works, we study the electronic structure and magnetic properties of the Pr-Ni-Bi half-Heusler systems based on density functional theory. We use the σ GGA + U scheme to consider the effects of on-site electron-electron interactions. Results show that in contrast to the rough estimation of the total magnetic moment of the unit cell, based on the Slater-Pauling behavior in the half-Heusler systems, this system has an antiferromagnetic ground state because of the localized Pr-f electrons. By increasing the magnitude of the effective U parameter, band-inversion occurs in the band structure of this system, which shows the possibility of topological state occurrence.

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Linear-scaling density-functional-theory technique: The density-matrix approach

Physical Review B ◽

10.1103/physrevb.53.7147 ◽

1996 ◽

Vol 53 (11) ◽

pp. 7147-7157 ◽

Cited By ~ 122

Author(s):

E. Hernández ◽

M. J. Gillan ◽

C. M. Goringe

Keyword(s):

Density Functional Theory ◽

Density Matrix ◽

Density Functional ◽

Linear Scaling ◽

Matrix Approach ◽

Functional Theory ◽

Theory Technique

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Recent Progress in Lattice Density Functional Theory

Computation ◽

10.3390/computation7040066 ◽

2019 ◽

Vol 7 (4) ◽

pp. 66 ◽

Cited By ~ 2

Author(s):

T. S. Müller ◽

W. Töws ◽

G. M. Pastor

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Particle Density ◽

Lattice Models ◽

Energy Functional ◽

Real Space ◽

Functional Theory ◽

Single Particle Density ◽

Lattice Density ◽

Lattice Density Functional Theory

Recent developments in the density-functional theory of electron correlations in many-body lattice models are reviewed. The theoretical framework of lattice density-functional theory (LDFT) is briefly recalled, giving emphasis to its universality and to the central role played by the single-particle density-matrix γ . The Hubbard model and the Anderson single-impurity model are considered as relevant explicit problems for the applications. Real-space and reciprocal-space approximations to the fundamental interaction-energy functional W [ γ ] are introduced, in the framework of which the most important ground-state properties are derived. The predictions of LDFT are contrasted with available exact analytical results and state-of-the-art numerical calculations. Thus, the goals and limitations of the method are discussed.

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TREATMENTS OF THE EXCHANGE ENERGY IN DENSITY-FUNCTIONAL THEORY

International Journal of Modern Physics B ◽

10.1142/s0217979208039344 ◽

2008 ◽

Vol 22 (14) ◽

pp. 2225-2239

Author(s):

TAMÁS GÁL

Keyword(s):

Density Functional Theory ◽

Ground State ◽

Density Functional ◽

Common Ground ◽

Particle Density ◽

Exchange Energy ◽

Density Functionals ◽

Simple Derivation ◽

Functional Theory ◽

Hartree Fock

Following a recent work [Gál, Phys. Rev. A64, 062503 (2001)], a simple derivation of the density-functional correction of the Hartree–Fock equations, the Hartree–Fock–Kohn–Sham equations, is presented, completing an integrated view of quantum mechanical theories, in which the Kohn–Sham equations, the Hartree–Fock–Kohn–Sham equations and the ground-state Schrödinger equation formally stem from a common ground: density-functional theory, through its Euler equation for the ground-state density. Along similar lines, the Kohn–Sham formulation of the Hartree–Fock approach is also considered. Further, it is pointed out that the exchange energy of density-functional theory built from the Kohn–Sham orbitals can be given by degree-two homogeneous N-particle density functionals (N = 1, 2, …), forming a sequence of degree-two homogeneous exchange-energy density functionals, the first element of which is minus the classical Coulomb-repulsion energy functional.

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