Questions tagged [dispersion-correction]
Questions related to corrections due to dispersion effects in matter modeling.
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Does the Grimme D3 correction improve band gaps of vdW heterostructures?
I am doing band structure calculations of 2 by 2 by 1 MoS2/MoSe2 van der Waals heterostructure in Quantum Espresso. I have noticed that adding Grimme DFT-D3 correction to PBE functional has very ...
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Set coordination number cutoff in CP2K's D3 dispersion
The D3 dispersion correction has 2 distance cutoff values. One for the calculation of coordination numbers, one for the energy contribution.
In other implementations, such as vasp and DFTB+ (tblite), ...
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How to obtain imaginary frequency polarizability?
I am trying to find a way to calculate $C_6$ dispersion coefficients for some atoms and molecules. In papers and textbooks, this quantity is introduced using the Casimir-Polder integral from the ...
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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? [closed]
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?
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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 ...
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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 ...
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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 ...
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