6. DFT vs (Post) HF Methods#
All methods discussed so far evaluate the energy of a system based on its wavefunction \(\Psi\); a purely mathematical object that lacks any direct physical interpretation. In the next two sets of exercises, you will explore a formalism that is based on a physical observable, called Density Functional Theory (DFT). Rather than linking observables to abstract wavefunctions, DFT relates any observable to a physical, measurable quantity, the electron density \(\rho\).
In the next two sets of exercises, you will assess the performance of various state-of-the-art density functionals in the prediction of reaction enthalpies and geometric properties, and you will compare your results to both wavefunction theory and experimental data. The first exercise constitutes more of a practical introduction; you will be provided with more ample theoretical information on DFT in the following week.
🎯 Learning goals
Compare accuracy and efficiency of electron density based methods to wavefunction based methods
Compare exchange-correlation functionals used in DFT calculations
Learn how frontier orbital visualization supports the analysis of electronic structure calculations
📖 Chapter in script
Chapter 8 - Density Functional Theory