Questions tagged [dispersion-correction]
Questions related to corrections due to dispersion effects in matter modeling.
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For what DFT functional is useless to add D3 or similar corrections?
I would like to know for which DF is useless to add dispersion corrections.
For example, I suppose that for the nonlocal density-based functionals such as wB97M-V it is unnecessary because the ...
6
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0
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Cutoff length for vdW correction in DFT calculation
In classical MD simulations of lattice structures, whenever we are trying to incorporate vdW corrections to the atomic force calculation, we need to set up cutoff length beyond which the vdW ...
8
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answer
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How might inclusion of a Grimme dispersion correction influence a simulation of a dense liquid that is not water?
I adapted an example first-principles water simulation to do simulations of liquid SiO2, but did not know what I was doing and did not remove a Grimme dispersion correction term.
It would be great to ...
13
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1
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Keesom and Debye forces in DFT
Do van der Waals corrected DFT functionals include Keesom and Deby corrections too or just London dispersion? Because when I look at these methods in detail, I see that there is just an attempt to ...
8
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1
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Should I add vdW interaction to estimate chemical potential of metallic elements?
I am considering layered oxides $\ce{LiCoO2}$. Previous papers suggested that vdW interaction should be added to get lattice parameters closer to experimental data. I would like to dope other elements ...
14
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Are dispersion correction methods for DFT (such as D3) useful for geometry optimization?
For what I know the DFT-D3 method or similar corrections that take into account dispersion effect, add this type of contribution through calculation of atom pairwise interactions at the end of an ...
8
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1
answer
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Calculation of dispersion energies for organometallic complexes with Gaussian
I've tried to calculate dispersion energies of some organometallic complexes with the Gaussian software using WB97XD/Gen (...
4
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0
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What are the TS, MBD keywords for new (5.4.+) VASP versions? [closed]
I tried IVDW = 2202 for MBD as mentioned on the website but I got the following error:
...
9
votes
1
answer
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SCAN-RVV10 geometry optimization
I'm using SCAN-RVV10 to optimize the hexagonal-BN but the optimized geometry doesn't look true as the calculated interlayer distance is far smaller than the experimental value(exp=3.35 Aangstrom, calc=...
5
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Dispersion correction and band structure
Let's say I optimized geometry with PBE+D3. I want to carry out band structure calculation with HSE06, should I add the dispersion correction to the band structure calculation or not?
I tried both and ...
10
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1
answer
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How does MBD (MBD-NL) differ from DFT-TS?
Is anyone familiar with Tkatchenko's new MBD-NL method? How does it differ from DFT-TS? I couldn't understand everything from the paper.
10
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2
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Band structure with additive dispersion methods
Let's say I optimized geometry with PBE+D3, does it matter if I make single point bandstructure calculation with just PBE or PBE+D3 since D3 is a additive method.
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Best vdW correction functional for transition metal dichalcogenides
For relaxation of transition metal dichalcogenides (e.g.: WS2) using the VASP code, what is the best choice for vdW correction method (e.g.: DFT-D2, DFT-D3 or optB88-vdW) that can give you good ...
14
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answer
761
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Difference between Van der Waals (DFT-D and DFT-D3) corrections in ab-initio calculations
In Kohn-Sham DFT calculations, Van der Waals corrections are often implemented in the structure optimization calculations because the typical functionals such as LDA and GGA are found to not treat ...
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What are the different ways of calculating dispersion constants?
There are many different dispersion corrections out there. The most famous is D3 [1] (and the new D4 [2]), but there's probably other approaches too. The dispersion energy can be written as:
$$
E_{\...