Seminarium Fizyki Materii Skondensowanej

To answer the fundamental question posed in the title I will first discussthe concept of correlations in electronic systems and then introduce thestate-of-the-art DFT+DMFT scheme, which combines density functional theory(DFT) with the many-body dynamical mean-field theory (DMFT). Then I willexplain how to compute the total energy of correlated materials withinthis approach. One finds that the lattice stability of materials such asFe, FeSe (the simplest iron based superconductor), or V2O3 (the typicalexample of a system with Mott metal-insulator transition) can only beexplained if the local Coulomb repulsion between the electrons is includedexplicitly.