Can density functional theory describe the Mott insulator?
Density functional theory (DFT) is one of the most computationally tractable methods of solving the Schrödinger equation for atoms, molecules, and solids. It is such a valuable tool in theoretical chemistry and solid state physics that Walter Kohn and John Pople shared Nobel Prize for developing it. Yet there are many situations where DFT does not work well [1]. One of the most important of these situations is when the interactions and hence the correlations between electrons are strong. The poster child for strong electronic correlations is the Mott insulator – where the material would be a metal in the absence of electronic correlations, but in actual fact becomes an insulator. It is often stated that DFT cannot capture the physics of the Mott insulator. But, this is consequence of the approximations typically used in implementing DFT and not a fundamental limitation of the theory. In this project you will investigate the failings of DFT. You will investigate possible new functionals
