• last year
In density functional theory (DFT) calculations, a basis set is a set of mathematical functions used to describe the system's electron density and wave function. The basis set is typically a set of atomic orbitals that are centered on each atom in the system.

The choice of basis set in DFT calculations is important because it affects the accuracy and efficiency of the calculations. The basis set's size and complexity can affect the results' accuracy, with larger basis sets generally providing more accurate results. However, larger basis sets also require more computational resources and can make calculations slower.

Different basis sets are available for DFT calculations, including Gaussian-type (GTOs) and plane wave basis sets (PWBs). GTOs are typically used for molecular systems, while PWBs are used for periodic systems.

When choosing a basis set, it is important to consider the size and complexity of the system being studied and the level of accuracy required for the calculations. Generally, larger and more complex systems require larger and more sophisticated basis sets to achieve accurate results.

In addition, there are also standard basis sets that have been developed and tested for different types of systems and applications. These standard basis sets can be a good starting point for choosing a basis set for a particular system. For example, the popular basis sets for molecular calculations include the 6-31G(d), 6-311G(d,p), and cc-pVDZ basis sets.
___________________________________________________

Recommended