Local-density approximation self-interaction-corrected

Stampfl C, van de Walle C G, Vogel D, Kruger P and Pollmann J 2000 Native defects and impurities in InN First-principles studies using the local-density approximation and self-interaction and relaxation-corrected pseudopotentials Phys. Rev. B 61 R7846-9... 

Hamada, N. and Ohnishi, S. (1986) Self-interaction correction to the local-density approximation in the calculation of the energy band gaps of semiconductors based on the full-potential linearized augmented-plane-wave method, Phys. Rev., B34,9042-9044. 

While the LSD exchange-correlation hole is accurate for small interelec-tronic separations (Sect. 2.3), it is less satisfactory at large separations, as discussed in Sect. 2.5. For example, consider the hole for an electron which has wandered out into the classically-forbidden tail region around an atom (or molecule). The exact hole remains localized around the nucleus, and in Sect. 2.5 we give explicit results for its limiting form as the electron moves far away [19]. The LSD hole, however, becomes more and more diffuse as the density at the electron s position gets smaller, and so is quite incorrect. The weighted density approximation (WDA) and the self-interaction correction (SIC) both yield more accurate (but not exact) descriptions of this phenomenon. 

DPT schemes, which allow to calculate the electron affinities of atoms are based on the exact [59,60] and generalized (local) [61,62] exchange self-interaction-corrected (SIC) density functionals, treating the correlation separately in some approximation. Having better asymptotic behavior than GGA s, like in the improved SIC-LSD methods, one should obtain more... 

An interesting aspect of the density functional calculations of Penzar and Ekardt is that these include self-interaction corrections. It is well known that the local density approximation (LDA) to exchange and correlation effects is not sufficiently accurate to give reliable electron affinities of free atoms or clusters [47,48]. This defidency is due to the fact that, in a neutral atom for instance, the LDA exchange-correlation potential Vif (f) decays exponentially at large r, while the exact behavior should be — 1/r. As a consequence, some atomic and cluster anions become unstable in LDA. The origin of this error is the incomplete cancellation of the self-interaction part of the classical coulomb energy term... 

Harrison, J. G. (1987). Electron afilnities in the self-interactions-corrected local spin density approximation. J. Chem. Phys. 86,2849-2853. 

Self-interaction-corrected local spin density approximation... 

Another calculation for the complete series used a local spin-density approximation with self-interaction correction. Relativistic contributions AA had a dramatic effect (for Os A = 1.5, AA=—1.52eV) [11]. SCF-Xa-SW theory was applied for Ru, Rh, Pd [12], Ir, and Pt [13]. A preliminary many-body calculation for the Pd ion in its 4d °5s S ground state confirmed a positive value of A [14]. 

Here the first part is the electrostatic self-Coulomb interaction and the second part is the analog correction for the exchange-correlation part of the effective potential. Please note that both functionals depend on the total density n, and not on the spin densities as in the case of Perdew and Zunger who corrected the LSDA (Local Spin Density Approximation). Results for Cu are reproduced in Figure 1.15 [31]. Though with this simple functional quantitative agreement with experimental data is not to be expected, the experimentally observed shell effects in the electron affinity are qualitatively well reproduced. 

---