Problems with LEXCH tags in a mixed P0TCAR file

[szabla]

Hi,
I am using vasp.4.6.25. When I combine GGA POTCAR files for Cu and Xe the following message appears in my rec.txt file:

-----------------------------------------------------------------------------
| |
| EEEEEEE RRRRRR RRRRRR OOOOOOO RRRRRR ### ### ### |
| E R R R R O O R R ### ### ### |
| E R R R R O O R R ### ### ### |
| EEEEE RRRRRR RRRRRR O O RRRRRR # # # |
| E R R R R O O R R |
| E R R R R O O R R ### ### ### |
| EEEEEEE R R R R OOOOOOO R R ### ### ### |
| |
| You have build up your multi-ion-type POTCAR file out of POTCAR |
| files with incompatible specifications for the XC-types used to |
| generate the pseudopotential. This makes no sense at all!! What |
| I found is LEXCH = 2 for atom types <= 1 but LEXCH = 7 |
| was found for atom type = 2. Use identical XC-functionals for |
| the pseudopotential generation for all atom types, please ... ! |
| |
| ----> I REFUSE TO CONTINUE WITH THIS SICK JOB ..., BYE!!! <---- |
| |
-----------------------------------------------------------------------------

In fact the LEXCH tags are not 2 and 7 as it says but 91 and CA, for Cu and Xe respectively. While in the firs case the tag 91 is OK for GGA in the latter it is probably not.

In the original vasp GGA POTCAR file for Xe the tag LEXCH is set to CA which suggests that it is LDA rather than GGA. I would be very gratefull if you could tell me how to solve that problem.

[admin]

you should be very careful not to mix potentials with different XC in one calculation, this will crash immediately: please switch to a XC-type for which you can find appropriate PPs for all input atoms, or contact vasp.materialphysik@univie.ac.at if you cannot find them at the server
[ Edited Thu Oct 19 2006, 05:45PM ]