RECENT ACHIEVEMENTS OF DENSITY FUNCTIONAL THEORY IN ELECTRONIC SYSTEMS

The main feature of the electronic systems in atoms, molecules and solids is that external potential as well as mutual interaction between electrons has the form of Coulomb potential. In such a case, the knowledge of the one-particle density determines not only the ground state energy of the electronic system but also the full Hamiltonian of the systems. Therefore, the very special properties of the Coulomb density allow for formulation of an exact time-independent density functional theory (DFT) of ground and excited states of Coulomb systems [1].

In recent years, the reliable DFT calculations have become a prerequisite for design of novel materials with required functionalities. The need for high accuracy predictions has induced very strong activity for search for better approximations to the exchange and correlation functionals. I will illustrate this trend by discussing the role of DFT calculations for prediction of the nanostructured gas-adsorbent materials (GAMs) [2]. The two main problems in the standard DFT approximations are: (i) spurious self-interaction, and (ii) impossibility to record for long-range dispersive van der Waals (vdW) forces. The recent proposals for functionals addressing these problems will be reviewed. The issue of vdW forces will be also exemplified with our own results for hydrogenated and fluorinated graphene on metallic and insulating substrates.

Finally, I would like to stress the role the DFT has played for development of modern materials science and point out areas of physico-chemistry for which the further progress without DFT is unthinkable.

[1] P. W. Ayers, M. Levy, and A. Nagy, Phys. Rev. A 85, 042518 (2013).

[2] C. Cazorla, Coordination Chemistry Reviews 300, 142 (2015).

Serdecznie zapraszamy
M. Kowal, W. Piechocki, L. Roszkowski, J. Skalski