All electron calculations in condensed matter: the GAPW approach

3 October 2005 (Mon), 3:30 pm - 5:00 pm

6F seminar room, Sengen site

Dr. Marcella Iannuzzi

Physical Chemistry Institute, University of Zurich

All electron calculations in condensed matter: the GAPW approach

Our recent work focused on the development of methods to perform Kohn--Sham calculations using accurate basis sets on large systems, including condensed matter systems (periodic boundary conditions). The Gaussian Augmented Plane Wave method (GAPW) is a hybrid method that combines the advantages of the plane waves approach with the expansion of the KS orbitals in terms of localized functions, thus achieving significant improvements in accuracy and efficiency. Moreover, it can be extended to all electron calculations, which are mandatory to reproduce with high accuracy those properties, such as magnetic response or the x-ray absorption/emission spectra, which depend critically on the details of the wavefunctions in the core regions. Some results are presented about x-ray spectroscopy simulations for water systems. For the calculation of properties like the excitation energies and the chemical shifts, we reformulated the generalized density functional perturbation theory in terms of the GAPW scheme. Preliminary results are given to demonstrate accuracy and performance of the method.

Dr. Yoshitaka Tateyama(館山佳尚)