Improved Slater approximation to SIC–OEP

We propose a simplification of the optimized effective potential (OEP) method applied to the self-interaction correction (SIC) on the local density approximation (LDA) in density-functional theory (DFT). The new scheme fulfills crucial formal key properties. It turns out to be simple and accurate. We apply the new method to a schematic model for a dimer molecule and to the C atom. We discuss observables which are especially sensitive to details of the SIC.