Density Functional Theory (DFT)
Density Functional Theory (DFT) postulates that the energy of a molecule can be calculated from the electron density rather than the wave function. The electron density requires less computational resources to determine than the wave function, so use of DFT has become a popular approach.
A "functional" is a function of a function. In this case, the exact density functional is not known exactly. As a result there have been many attempts to create density functionals that will provide superior accuracy and/or faster calculation. Some of the density functionals that have been developed are:
| Acronym |
Name |
Type |
Comment |
| B3LYP |
Becke 3-term functional with Lee, Yang, Parr exchange |
Hybrid |
Often used for organic molecules |
| BLYP |
Becke correlation functional with Lee, Yang, Parr exchange |
|
| B96 |
Becke 96 |
Gradient-corrected |
|
