Effect Of Self-interaction Correction Research Articles

Electron Localization Function and Compton Profiles of Cu2O.

The nature of bonding in the cubic cuprous oxide is studied by means of the theoretical tools, namely, the electron localization function and Compton profiles. The isotropic Compton profiles together with the anisotropies in the directional Compton profiles are presented. Taking free-atom Compton profiles, the charge-transfer model is also applied. The first-principles calculations based on the GGA are performed, and the self-interaction correction is incorporated, adopting the GGA+U approach. Both types of calculations are performed deploying the linearized augmented plane-wave (LAPW) method. The effect of self-interaction correction on the electron localization function, Compton profiles, and anisotropies is discussed. The electron localization function reveals ionic behavior in the (110) plane and covalent nature in the Cu-O bond intersecting plane. The GGA+U exhibits more covalent nature. The two LAPW calculations of the Compton profiles show better agreement with the available experimental data than the free-atom profiles. Among all of the calculations undertaken, the GGA+U shows the best agreement with the experiment. The GGA+U calculation shows more anisotropic behavior in directional Compton profiles.

Anomalous length dependence of conductance of aromatic nanoribbons with amine anchoring groups

Two sets of aromatic nanoribbons, based around a common hexagonal scaffolding, with single and dual terminal amine groups have been considered as potential molecular wires in a junction formed by gold leads. Charge transport through the two-terminal device has been modeled using density functional theory (with and without self-interaction correction) and the nonequilibrium Green's function method. The effects of wire length, multiple terminal contacts, and pathways across the junction have been investigated. For nanoribbons with the oligopyrene motif and conventional single amine terminal groups, an increase in the wire length causes an exponential drop in the conductance. In contrast, for the nanoribbons with the oligoperylene motif and dual amine anchoring groups the predicted conductance rises with the wire length over the whole range of investigated lengths. Only when the effects of self-interaction correction are taken into account, the conductance of the oligoperylene ribbons exhibits saturation for longer members of the series. The oligoperylene nanoribbons, with dual amine groups at both terminals, show the potential to fully harness the highly conjugated system of $\ensuremath{\pi}$ molecular orbitals across the junction.

Magnetizabilities at Self-Interaction-Corrected Density Functional Theory Level.

Using a recent high-quality ab initio coupled cluster benchmark set for magnetizabilities, we assess the performance of a set of density functionals, representing different levels of complexity, from the local density approximation (LDA), via generalized gradient approximations (GGA's) to kinetic energy density including meta-GGA's. The effect of self-interaction correction (SIC) is remarkable and, in most cases, leads to a significant error reduction, revealing the sensitivity of magnetizability toward a physically sound exchange-correlation potential.

Effects of self-interaction correction on momentum density in copper

The full-potential linearized APW (FLAPW) method is employed to find out effects of introducing the self-interaction correction (SIC) on the band structure, the Fermi surface geometry, electron wavefunctions and Compton profiles. Introduction of the SIC lowers and narrows the d bands. As the results, the theoretical Compton profiles are brought into a better agreement with the experimental profiles on one hand, and the area of the Fermi surface neck at the L point becomes too small to explain the dHvA result on the other hand.

Effects of Self-Interaction Correction on Compton Profiles of Diamond and Silicon

The full-potential linearized augmented-plane-wave (FLAPW) method is employed to find out effects of introducing the self-interaction correction (SIC) on the band structures, electron wavefunctions and Compton profiles of both diamond and silicon. To examine the computed results high-resolution Compton profiles of silicon along the , and directions are measured. In the case of silicon, it is found that theoretical Compton profiles computed with the SIC are in better agreement with the measured profiles when their first derivatives are compared. Although the effects of the SIC is much larger in the case of diamond, the theoretical prediction is to be tested by future high-resolution Compton profile measurements.

A density functional study of the simplest hydrogen abstraction reaction. Effect of self-interaction correction

Twenty-four different local and gradient-corrected density functional methods were used in a study of the reaction H+H 2→H 2+H. Barrier heights were calculated with a large basis set. The results were compared to those obtained by ab initio methods and experiment. It was found that conventional Kohn-Sham methods consistently and significantly understimate the reaction barrier. In particular, the local-spin density approximation (LSDA) in unmodified form completely fails, predicting H 3 to be a stable species. However, the inclusion of a self-interaction correction restores the correct qualitative features of the potential surface, and generally leads to reasonable results when pairing a gradient-corrected exchange functional with a correlation functional.