Grimme’s Dispersion DFT-D3 in Gaussian #CompChem

I was just asked if it is possible to perform DFT-D3 calculations in Gaussian and my first answer was to use the following  keyword:

EmpiricalDispersion=GD3

which is available in G16 and G09 only in revision D, apparently.

There are also some overlays that can be used to invoke the use dispersion in various scenarios:

IOp(3/74=x) Exchange and Correlation Potentials

-77

-76

-60

-59

DSD-PBEP86 (double hybrid, DFT-D3).

PW6B95-D3.

B2PLYP-D3 (double hybrid, DFT-D3).

B97-D (DFT-D3).

IOp(3/76=x) Mixing of HF and DFT.

-33 PW6B95 and PW6B95-D3 coefficients.

IOp(3/124=x) Empirical dispersion term.

30

40

50

Force dispersion type 3 (Grimme DFT-D3).

Force dispersion type 4 (Grimme DFT-D3(BJ)).

Force dispersion type 5 (Grimme D3, PM7 version).

 

The D3 correction method of Grimme defines the van der Waals energy like:

$\displaystyle E_{\rm disp} = -\frac{1}{2} \sum_{i=1}^{N_{at}} \sum_{j=1}^{N_{at...
...{6ij}} {r_{ij,{L}}^6} +f_{d,8}(r_{ij,L})\,\frac{C_{8ij}} {r_{ij,L}^8} \right ),$

where coefficients $ C_{6ij}$ are adjusted depending on the geometry of atoms i and j. The damping D3 function for is:

$\displaystyle f_{d,n}(r_{ij}) = \frac{s_n}{1+6(r_{ij}/(s_{R,n}R_{0ij}))^{-\alpha_{n}}},$

where the values of s are adjustable parameters fit for the exchange-correlation functionals used in each calculation.

About joaquinbarroso

Computational and theoretical chemist in his early forties, in love with life, science, baseball, and literature. Science literacy makes us responsible citizens, it is therefore a scientific duty to talk, write, and engage with the general public; as Feynman said, if you find science boring, your learning from the wrong teacher. "Make like a molecule and react!"

Posted on March 8, 2017, in Computational Chemistry, DFT, Gaussian, Theoretical Chemistry, White papers and tagged , , , , , , , , , , , . Bookmark the permalink. 5 Comments.

  1. Very useful. Thank you so much.

  2. how can apply Dispersion DFT-D2 in Gaussian 09?

  3. Francisca Benítez

    In ORCA I can use HF with dispersion, is that also possible for G16?
    It’s for a benchmark, don’t judge me 😉

    • Hola Francisca!

      No judgement here LOL I don’t see why not. If you have the latest G16 revision you might try with EmpiricalDispersion=GD3, but you can also go to Grimme’s webpage, load your file, select method = HF, and get the empirical dispersion added to your molecule (http://wwwtc.thch.uni-bonn.de/); not really useful for a benchmark, I know but is worth knowing it.

      I hope this helps!

  1. Pingback: Post Calculation Addition of Empirical Dispersion – Fixing interaction energies | Dr. Joaquin Barroso's Blog

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