DFT-D3: Difference between revisions

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


where <math>R_{0ij} = \sqrt{\frac{C_{8ij}}{C_{6ij}}}</math>, the parameters <math>\alpha_6</math>, <math>\alpha_8</math>, <math>s_{R,8}</math> and <math>s_{6}</math> are fixed at values of 14, 16, 1, and 1, respectively, while <math>s_{8}</math> and <math>s_{R,6}</math> are adjustable parameters whose values depend on the choice of the exchange-correlation functional. The DFT-D3(zero) method is invoked by setting {{TAG|IVDW}}=11. Optionally, the following parameters can be user-defined (the given values are the default values):
where <math>R_{0ij} = \sqrt{\frac{C_{8ij}}{C_{6ij}}}</math>, the parameters <math>\alpha_6</math>, <math>\alpha_8</math>, <math>s_{R,8}</math> and <math>s_{6}</math> are fixed at values of 14, 16, 1, and 1, respectively, while <math>s_{8}</math> and <math>s_{R,6}</math> are adjustable parameters whose values depend on the choice of the exchange-correlation functional. The DFT-D3(zero) method is invoked by setting {{TAG|IVDW}}=11. Optionally, the following parameters can be user-defined (the given values are the default ones):


*{{TAG|VDW_RADIUS}}=50.2 : cutoff radius (in <math>\AA</math>) for pair interactions considered in the equation of <math> E_{\mathrm{disp}}</math>
*{{TAG|VDW_RADIUS}}=50.2 : cutoff radius (in <math>\AA</math>) for pair interactions considered in the equation of <math> E_{\mathrm{disp}}</math>
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:<math>f_{d,n}(r_{ij}) = \frac{s_n\,r_{ij}^n}{r_{ij}^n + (a_1\,R_{0ij}+a_2)^n} </math>
:<math>f_{d,n}(r_{ij}) = \frac{s_n\,r_{ij}^n}{r_{ij}^n + (a_1\,R_{0ij}+a_2)^n} </math>


with <math>s_6=1</math> and <math>a_1</math>, <math>a_2</math>, and <math>s_8</math> being adjustable parameters.
with <math>s_6=1</math> and <math>a_1</math>, <math>a_2</math>, and <math>s_8</math> being adjustable parameters.
This variant of DFT-D3 method (DFT-D3(BJ)) is invoked by setting {{TAG|IVDW}}=12. As before, the parameters {{TAG|VDW_RADIUS}} and {{TAG|VDW_CNRADIUS}} can be used to change the default values for the cutoff radii. The parameters of the damping function can be controlled using the following tags:
This variant of DFT-D3 method (DFT-D3(BJ)) is invoked by setting {{TAG|IVDW}}=12. As before, the parameters {{TAG|VDW_RADIUS}} and {{TAG|VDW_CNRADIUS}} can be used to change the default values for the cutoff radii. The parameters of the damping function can be controlled using the following tags:


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*{{TAG|VDW_A2}}=[real]
*{{TAG|VDW_A2}}=[real]


{{NB|mind|The default values for the damping function parameters are available for the following/= functionals: PBE ({{TAG|GGA}}), RPBE ({{TAG|GGA}}), revPBE ({{TAG|GGA}}) and PBEsol ({{TAG|GGA}}). If another functional is used, the user has to define these parameters via the corresponding tags in the {{TAG|INCAR}} file. The up-to-date list of parametrized DFT functionals with recommended values of damping function parameters can be found on the webpage https://www.chemie.uni-bonn.de/pctc/mulliken-center/software/dft-d3/.}}
{{NB|mind|
{{NB|mind|The DFT-D3 method has been implemented in VASP by Jonas Moellmann based on the dftd3 program written by Stefan Grimme, Stephan Ehrlich and Helge Krieg. If you make use of the DFT-D3 method, please cite reference {{cite|grimme:jcp:10}}. When using DFT-D3(BJ) references {{cite|grimme:jcp:10}} and {{cite|grimme:jcc:11}} should also be cited.}}
*The default values for the damping function parameters are available for several {{TAG|GGA}} (PBE, RPBE, revPBE and PBEsol), {{TAG|METAGGA}} (TPSS, M06L and SCAN) and [[list_of_hybrid_functionals|hybrid]] (B3LYP and PBEh/PBE0) functionals, as well as [[list_of_hybrid_functionals|Hartree-Fock]]. If another functional is used, the user has to define these parameters via the corresponding tags in the {{TAG|INCAR}} file. The up-to-date list of parametrized DFT functionals with recommended values of damping function parameters can be found on the webpage https://www.chemie.uni-bonn.de/grimme/de/software/dft-d3/ and follow the link "List of parametrized functionals").
 
*The DFT-D3 method has been implemented in VASP by Jonas Moellmann based on the dftd3 program written by Stefan Grimme, Stephan Ehrlich and Helge Krieg. If you make use of the DFT-D3 method, please cite reference {{cite|grimme:jcp:10}}. When using DFT-D3(BJ) references {{cite|grimme:jcp:10}} and {{cite|grimme:jcc:11}} should also be cited. Also carefully check the more extensive list of references found on  https://www.chemie.uni-bonn.de/grimme/de/software/dft-d3/.}}


== Related tags and articles ==
== Related tags and articles ==
{{TAG|VDW_RADIUS}},
{{TAG|VDW_CNRADIUS}},
{{TAG|VDW_S8}},
{{TAG|VDW_SR}},
{{TAG|VDW_A1}},
{{TAG|VDW_A2}},
{{TAG|IVDW}},
{{TAG|IVDW}},
{{TAG|IALGO}},
{{TAG|DFT-D2}},
{{TAG|DFT-D2}},
{{TAG|Tkatchenko-Scheffler method}},
[[DFT-D4]]
{{TAG|Tkatchenko-Scheffler method with iterative Hirshfeld partitioning}},
{{TAG|Self-consistent screening in Tkatchenko-Scheffler method}},
{{TAG|Many-body dispersion energy}},
{{TAG|dDsC dispersion correction}}


== References ==
== References ==

Latest revision as of 13:14, 5 July 2024

In the DFT-D3 method of Grimme et al.[1], the following expression for the vdW-dispersion energy-correction term is used:

Unlike in the method DFT-D2, the dispersion coefficients are geometry-dependent as they are adjusted on the basis of the local geometry (coordination number) around atoms and . In the zero-damping variant of the DFT-D3 method (DFT-D3(zero)), the damping function reads:

where , the parameters , , and are fixed at values of 14, 16, 1, and 1, respectively, while and are adjustable parameters whose values depend on the choice of the exchange-correlation functional. The DFT-D3(zero) method is invoked by setting IVDW=11. Optionally, the following parameters can be user-defined (the given values are the default ones):

  • VDW_RADIUS=50.2 : cutoff radius (in ) for pair interactions considered in the equation of
  • VDW_CNRADIUS=20.0 : cutoff radius (in ) for the calculation of the coordination numbers
  • VDW_S8=[real] : damping function parameter
  • VDW_SR=[real] : damping function parameter

Alternatively, the Becke-Johnson (BJ) damping can be used in the DFT-D3 method[2]:

with and , , and being adjustable parameters. This variant of DFT-D3 method (DFT-D3(BJ)) is invoked by setting IVDW=12. As before, the parameters VDW_RADIUS and VDW_CNRADIUS can be used to change the default values for the cutoff radii. The parameters of the damping function can be controlled using the following tags:


Mind:
  • The default values for the damping function parameters are available for several GGA (PBE, RPBE, revPBE and PBEsol), METAGGA (TPSS, M06L and SCAN) and hybrid (B3LYP and PBEh/PBE0) functionals, as well as Hartree-Fock. If another functional is used, the user has to define these parameters via the corresponding tags in the INCAR file. The up-to-date list of parametrized DFT functionals with recommended values of damping function parameters can be found on the webpage https://www.chemie.uni-bonn.de/grimme/de/software/dft-d3/ and follow the link "List of parametrized functionals").
  • The DFT-D3 method has been implemented in VASP by Jonas Moellmann based on the dftd3 program written by Stefan Grimme, Stephan Ehrlich and Helge Krieg. If you make use of the DFT-D3 method, please cite reference [1]. When using DFT-D3(BJ) references [1] and [2] should also be cited. Also carefully check the more extensive list of references found on https://www.chemie.uni-bonn.de/grimme/de/software/dft-d3/.

Related tags and articles

VDW_RADIUS, VDW_CNRADIUS, VDW_S8, VDW_SR, VDW_A1, VDW_A2, IVDW, DFT-D2, DFT-D4

References