Density functional method - Principles and applications

An overview of the main concepts of Density Functional Theory from a historical perspective is given. Most popular techniques of solving DFT equations currently used in chemistry are listed. Applications of the DFT method to study chemical reactions using various levels of DFT theory are discussed. Local DFT is successful in predicting molecular structures with covalent bonds. However in general it should not be used to study energetics of reactions and systems with weak interactions. The next level of theory, nonlocal DFT, is a preferable choice for the study of thermochemistry. Investigation of reaction barriers may require a higher level of theory, so called hy brid methods that use a portion of the exact Hartree-Fock exchange.