LMIXTAU: Difference between revisions

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{{TAGDEF|LMIXTAU|.TRUE. {{!}} .FALSE.|.FALSE.}}
{{TAGDEF|LMIXTAU|.TRUE. {{!}} .FALSE.|.FALSE.}}


Description: send the kinetic energy density through the density mixer as well.
Description: send the kinetic-energy density through the [[Density mixing|density mixer]] as well.
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For the density mixing schemes to work reliably, the charge density mixer must be aware of all quantities that affect the total energy during the self-consistency cycle. For a standard DFT functional, this is solely the charge density. In case of meta-GGAs, however, the total energy depends on the kinetic energy density as well.
In many cases, the [[Density mixing|density-mixing scheme]] works well enough without passing the kinetic-energy density through the mixer. Therefore VASP uses {{TAG|LMIXTAU}}=.FALSE. per default. However, when the self-consistency cycle fails to converge for one of the algorithms exploiting [[Density mixing|density mixing]], e.g, {{TAG|IALGO}}=38 or 48, we recommend setting {{TAG|LMIXTAU}}=.TRUE..


In many cases the density mixing scheme works well enough without passing the kinetic energy density through the mixer, which is why {{TAG|LMIXTAU}}=.FALSE., per default. However, when the selfconsistency cycle fails to converge for one of the density-mixing algorithms (for instance, {{TAG|IALGO}}=38 or 48), one may set {{TAG|LMIXTAU}}=.TRUE. to have VASP pass the kinetic energy density through the mixer as well.
== Related tags and articles ==
This sometimes helps to cure convergence problems in the selfconsistency cycle.
 
== Related Tags and Sections ==
{{TAG|METAGGA}},
{{TAG|METAGGA}},
{{TAG|LMAXTAU}}
{{TAG|LMAXTAU}}
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{{sc|LMIXTAU|Examples|Examples that use this tag}}
{{sc|LMIXTAU|Examples|Examples that use this tag}}
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[[The_VASP_Manual|Contents]]


[[Category:INCAR]][[Category:XC Functionals]][[Category:metaGGA]][[Category:Density Mixing]]
[[Category:INCAR tag]][[Category:Exchange-correlation functionals]][[Category:meta-GGA]][[Category:Electronic minimization]][[Category:Density mixing]]

Latest revision as of 09:31, 7 June 2022

LMIXTAU = .TRUE. | .FALSE.
Default: LMIXTAU = .FALSE. 

Description: send the kinetic-energy density through the density mixer as well.


In many cases, the density-mixing scheme works well enough without passing the kinetic-energy density through the mixer. Therefore VASP uses LMIXTAU=.FALSE. per default. However, when the self-consistency cycle fails to converge for one of the algorithms exploiting density mixing, e.g, IALGO=38 or 48, we recommend setting LMIXTAU=.TRUE..

Related tags and articles

METAGGA, LMAXTAU

Examples that use this tag