Band-structure calculation using meta-GGA functionals: Difference between revisions

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[[:Category:Band structure |Band-structure calculations]] for [[:Category:Meta-GGA|meta-GGA functionals]] require multiple steps. Below we give a step-by-step introduction and an example. Additionally, we provide some advice to reduce computational and human effort.
For [[:Category:Band structure|band-structure calculations]] with [[:Category:Meta-GGA|meta-GGA functionals]], follow the same procedure as for [[Band-structure_calculation_using_hybrid_functionals|band-structure calculations using hybrid functionals]]. The reason is that a regular k mesh has to be provided in order to compute the kinetic-energy density.
 
== Step-by-step instructions ==
 
For [[:Category:Meta-GGA|meta-GGA functionals]], the Hamiltonian cannot be expressed in terms of the electronic charge density alones, but requires also the kinetic-energy density. Instead, the Kohn-Sham orbitals on a regular '''k''' mesh are required for any calculation within the [[Hybrid functionals: formalism|formalism of hybrid functionals]]. The regular '''k''' mesh must be supplied in the {{FILE|KPOINTS}} file. Consequently, restarting a hybrid calculation requires the {{FILE|WAVECAR}} file of the previous self-consistent-field (SCF) run. This is in contrast to [[GGA|density-functional theory]] (DFT), where the electronic charge density written to the {{FILE|CHGCAR}} file suffices to restart a DFT calculation. In order to reach convergence more quickly, it is good practice to first compute the DFT result in a SCF calculation.
 


==Related tags and articles==
==Related tags and articles==
{{FILE| KPOINTS}}, {{FILE| KPOINTS_OPT}}
{{FILE| KPOINTS}}, {{FILE| KPOINTS_OPT}}, [[Band-structure calculation using hybrid functionals]]


== References ==
== References ==


[[Category:Meta-GGA]][[Category:Band structure |Band structure]][[Category:Howto|Howto]]
[[Category:Meta-GGA]][[Category:Band structure |Band structure]][[Category:Howto|Howto]]

Latest revision as of 13:54, 19 July 2022

For band-structure calculations with meta-GGA functionals, follow the same procedure as for band-structure calculations using hybrid functionals. The reason is that a regular k mesh has to be provided in order to compute the kinetic-energy density.

Related tags and articles

KPOINTS, KPOINTS_OPT, Band-structure calculation using hybrid functionals

References