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We introduce a spectral density functional theory which can be used to compute energetics and spectra of real strongly--correlated materials using methods, algorithms and computer programs of the electronic structure theory of solids. The approach considers the total free energy of a system as a functional of a local electronic Green function which is probed in the region of interest. Since we have a variety of notions of locality in our formulation, our method is manifestly basis--set dependent. However, it produces the exact total energy and local excitational spectrum provided that the exact functional is extremized. The self--energy of the theory appears as an auxiliary mass operator similar to the introduction of the ground--state Kohn--Sham potential in density functional theory. It is automatically short--ranged in the same region of Hilbert space which defines the local Green function. We exploit this property to find good approximations to the functional. For example, if electronic self--energy is known to be local in some portion of Hilbert space, a good approximation to the functional is provided by the corresponding local dynamical mean--field theory. A simplified implementation of the theory is described based on the linear muffin--tin orbital method widely used in electronic strucure calculations. We demonstrate the power of the approach on the long--standing problem of the anomalous volume expansion of metallic plutonium.
The LDA+DMFT method is a very powerful tool for gaining insight into the physics of strongly correlated materials. It combines traditional ab-initio density-functional techniques with the dynamical mean-field theory. The core aspects of the method ar
We present a review of the basic ideas and techniques of the spectral density functional theory which are currently used in electronic structure calculations of strongly-correlated materials where the one-electron description breaks down. We illustra
The ground state electronic structures of the actinide oxides AO, A2O3 and AO2 (A=U, Np, Pu, Am, Cm, Bk, Cf) are determined from first-principles calculations, using the self-interaction corrected local spin-density (SIC-LSD) approximation. Emphasis
We review the basic ideas of the dynamical mean field theory (DMFT) and some of the insights into the electronic structure of strongly correlated electrons obtained by this method in the context of model Hamiltonians. We then discuss the perspectives
Vanadium disulfide (VS_{2}) attracts elevated interests for its charge-density wave (CDW) phase transition, ferromagnetism, and catalytic reactivity, but the electronic structure of monolayer has not been well understood yet. Here we report synthesis