LOCPOT: Difference between revisions

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The {{TAG|LOCPOT}} file stores the local potential (in eV).
The [[LOCPOT]] file stores the local potential <math>V_{\text{LOCPOT}}(\mathbf{r})</math> (in eV) given by:


To write this file, the line
<math>
V_{\text{LOCPOT}}(\mathbf{r}) =
V(\mathbf{r}) +
\int \frac{n(\mathbf{r'})}{|\mathbf{r}-\mathbf{r'}|}d\mathbf{r'}+
V_{\text{XC}}(\mathbf{r})
</math>


LVTOT = .TRUE.
where <math>V(\mathbf{r})</math> is the ionic potential,
the second term is the Hartree potential and
<math>V_{\text{XC}}(\mathbf{r})</math> is the exchange-correlation potential.


must be set in the {{TAG|INCAR}} file. Depending on {{TAG|LVHAR}} the total local
To write this file, {{TAG|LVTOT}}=.TRUE. or {{TAG|LVHAR}}=.TRUE. must be set in the [[INCAR]] file.
Kohn-Sham potential ({{TAG|LVHAR}}=.FALSE.) or the sum of the Hartree and ionic potential ({{TAG|LVHAR}}=.FALSE.) is written to the LOCPOT file. From VASP.5.2.12 onwards, {{TAG|LVTOT}}=.TRUE. writes the local potential ''including'' the exchange-correlation contribution on {{TAG|LOCPOT}}, since {{TAG|LVHAR}} defaults  to .FALSE.
If {{TAG|LVHAR}}=.TRUE. the <math>V_{\text{XC}}(\mathbf{r})</math> is not included in <math>V_{\text{LOCPOT}}(\mathbf{r})</math>.


MIND: {{TAG|LVHAR}} was added at some point in vasp.5.1.12, please check whether your version supports this tag (the tag is written out at the beginning of the OUTCAR file).
The [[LOCPOT]] file format is similar to that of the {{TAG|CHGCAR}} file but it does not have the same data arrangement.
Versions not supporting {{TAG|LVHAR}} might write either the total Kohn-Sham potential or the electrostatic potential. Please check  main.F by searching for ''LEXCHG=-1'' in main.F. If the line ''LEXCHG=-1'' is commented out, the exchange-correlation potential is added, whereas if the line is present, only the electrostatic potential is written to the file.
 
The {{TAG|LOCPOT}} file format is similar to that of the {{TAG|CHGCAR}} file but it does not have the same data arrangement.
For spin unpolarized calculations it contains a single dataset with the potential.
For spin unpolarized calculations it contains a single dataset with the potential.
For collinear spin calculations (ISPIN=2), it contains two datasets: spin up and spin down.
For collinear spin calculations (ISPIN=2), it contains two datasets: spin up and spin down.
For noncollinear calculations (LNONCOLLINEAR=.TRUE.), it contains four datasets with spinor representation of the potential.
For noncollinear calculations (LNONCOLLINEAR=.TRUE.), it contains four datasets with spinor representation of the potential.


 
<em>Note for versions older than vasp.5.1.12</em>: please check whether your version supports this tag (it is written out at the beginning of the OUTCAR file). Versions not supporting {{TAG|LVHAR}} might or not add <math>V_{\text{XC}}(\mathbf{r})</math>. Please check this by searching for <tt>LEXCHG=-1</tt> in <tt>main.F</tt>. If the line <tt>LEXCHG=-1</tt> is commented out <math>V_{\text{XC}}(\mathbf{r})</math> is added otherwise it is not.
----
 
[[Category:Files]][[Category:Output Files]]

Revision as of 19:40, 12 February 2021

The LOCPOT file stores the local potential (in eV) given by:

where is the ionic potential, the second term is the Hartree potential and is the exchange-correlation potential.

To write this file, LVTOT=.TRUE. or LVHAR=.TRUE. must be set in the INCAR file. If LVHAR=.TRUE. the is not included in .

The LOCPOT file format is similar to that of the CHGCAR file but it does not have the same data arrangement. For spin unpolarized calculations it contains a single dataset with the potential. For collinear spin calculations (ISPIN=2), it contains two datasets: spin up and spin down. For noncollinear calculations (LNONCOLLINEAR=.TRUE.), it contains four datasets with spinor representation of the potential.

Note for versions older than vasp.5.1.12: please check whether your version supports this tag (it is written out at the beginning of the OUTCAR file). Versions not supporting LVHAR might or not add . Please check this by searching for LEXCHG=-1 in main.F. If the line LEXCHG=-1 is commented out is added otherwise it is not.