Questions tagged [dispersion-correction]
Questions related to corrections due to dispersion effects in matter modeling.
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Does the relaxed density (and therefore the relaxed orbitals) depend on the final energy in OO-DHDF+D calculations?
During an OO-RI-ωB97X-2-D2 calculation on ORCA, the non-dispersion-corrected OO-DHDF part of the calculation is performed, the D2 dispersion correction energy added to the resulting OO-DHDF energy, ...
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How I can consider Van der Waals interactions between two materials in Quantum ESPRESSO?
I'm working on a hybrid system (with two different materials). Could you tell me how I can take into consideration the Van der Waals interaction between them?
- 329
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Choosing the right basis set for describing vdW-interactions with DFT-D3
I want to do some DFT calculations for structures of protonated alkaloid dimers. I know that a method of choice when vdW interactions are involved is the use of dispersion corrections. But now I am ...
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Electronic Convergence Issues with Nonlocal vdW-DF Functionals (in VASP)
Compared to say the DFT-D3 type of dispersion corrections (set with IVDW in VASP), I've found the nonlocal vdW-DF functionals (described here in the VASP Wiki) to be much more difficult to converge ...
- 1,014
3
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1
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DFT-D2 calculations in VASP and Gaussian
We are planning on comparing the results of Quantum dots and Bulk materials for our systems so we are planning to use Gaussian for QD and VASP for Bulk. Considering that we will be comparing their ...
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Are dispersion constant calculated differently for elements that are heavier than Xe?
How does one obtain the value of dispersion coefficient $C_6$ for elements that come after Xe. I am going through the original paper [1]. I can see that:
$$\tag{1}C^a_6 = 0.05N(I^a \alpha^a),$$
where $...
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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 ...
- 1,459
7
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Cutoff length for vdW correction in DFT calculation [closed]
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 ...
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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 ...
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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 ...
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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 ...
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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 ...
- 1,459
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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 (...
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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:
...
- 1,041
10
votes
1
answer
271
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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=...
- 1,041
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votes
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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 ...
- 1,041
10
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1
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333
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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.
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11
votes
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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5
votes
1
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425
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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 ...
- 5,643
17
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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_{\...
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