Nonlocal exchange correlation in screened-exchange density functional methods

Impact ionization in GaAs: a screened exchange density functional approach

Results are presented of a fully ab-initio calculation of impact ionization rates in GaAs within the density functional theory framework, using a screened– exchange formalism and the highly precise all-electron full-potential linearized augmented plane wave (FLAPW) method. The calculated impact ionization rates show a marked orientation dependence in k space, indicating the strong restrictions ...

Density-functional approximations for exchange and correlation

Density-functional theory (DFT) is based on two pivotal theorems due to Hohenberg and Kohn [1]. The first theorem states that the ground-state density ρ(r) of a system of electrons uniquely determines the Hamiltonian and hence all properties that can be derived from it. Using mathematical language we can say that the total electronic energy of the system is a functional of the electron density,

Alternative separation of exchange and correlation in density-functional theory

Introduction to Density Functional Theory and Exchange-Correlation Energy Functionals

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Effects of d-electrons in pseudopotential screened-exchange density functional calculations

We report a theoretical study on the role of shallow d states in the screened-exchange local density approximation (sX-LDA) band structure of binary semiconductor systems. We found that inaccurate pseudo-wavefunctions can lead to 1) an overestimation of the screened-exchange interaction between the localized d states and the delocalized higher energy s and p states and 2) an underestimation of ...