CCL: Complete basis set extrapolation, but with DFT methods


Hello hello,

It is not common to do DFT CBS-extrapolation, as usually it's not necessary. Combined with laziness (it wouldn't actually take that much time) you seldom see extrapolations. For achieving the complete basis-set limit, it is useful/used, though, both at Hartree-Fock and DFT levels. When the system is too large to do a QZ calculation, a two-point [D,T]Z-extrapolation might be in place as well.

For some good discussion and extrapolation formulae, see, e.g., Frank Jensen's papers:
"Polarization consistent basis sets. II. Estimating the Kohn–Sham basis set limit", https://doi.org/10.1063/1.1465405
"Estimating the Hartree—Fock limit from finite basis set calculations", https://doi.org/10.1007/s00214-005-0635-2

Cheers,
    Mikael


On 12.6.2018 05:27, Guzman, Francisco fg58()njit.edu wrote:
Hello CCL'ers,

Using electron correlation methods, such as CCSD(T), it is a very common approach to extrapolate single point energies to the complete basis set limit (CBS). 

However, is it also common place to apply the the CBS procedure, but to instead use a DFT method such as wb97x, PBE0, or M06-2X?

Best,

--
Francisco Guzman
PhD Candidate
Otto H. York Department of Chemical, Biological and Pharmaceutical Engineering
New Jersey Institute of Technology

--
 Dr. Mikael Johansson
 Academy Researcher
 Department of Chemistry
 University of Helsinki
 http://blogs.helsinki.fi/johansson-group