More precise estimation of the greedy algorithm complexity for a special case of the set cover problem is given in this paper. Introduction The greedy heuristic is the most used for optimization problems. The general approach is as follows: repeatedly, a procedure that minimizes (maximizes) the local increase of the objective function is applied. In some cases the greedy strategy guarantees the...

Polarized measurements of oriented single crystals can be used to simplify the interpretation of X-ray absorption near edge structure (XANES) spectra by permitting a direct determination of the symmetry properties of a particular transition. We have utilized this technique to study the XANES spectra for several first-row transition metal complexes. Applications to the weak, ls+3d transition, to...

We have developed an efficient computational scheme utilizing the real-space finite-difference formalism and the projector augmented-wave PAW method to perform precise first-principles electronic-structure simulations based on the density-functional theory for systems containing transition metals with a modest computational effort. By combining the advantages of the time-saving double-grid tech...