Organizers: Sandor Kristyan, senior reserach advisor, Research Centre for Natural Sciences, (HUN-REN RCNS), H-1117 Budapest, Magyar Tudósok körútja 2, Hungary
Email: kristyan.sandor@ttk.mta.hu, kristyan.sandor@ttk.hu
The SCF convergence part of the HF-SCF method has been replaced by finding the stationary points of the electronic energy functional with Lagrange multipliers for ortho-normality constraints – which is a 4th order multivariable polynomial of the LCAO coefficients and Lagrange multipliers – directly with the help of Groebner basis in Buchberger’s algorithm, an algebraic geometry device. One-determinant approximations of ground and excited states are calculated for some molecular systems in the demonstrations with different multiplicity. The relation of our algorithm to the KS-DFT algorithm is also commented.