Page 1 of 1

Error with running MD calculations with dipole and electric field

Posted: Thu May 08, 2025 2:43 pm
by Abdulrahman_Allangawi

Dear all, I am running MD calculations on a system with a total charge of +1. I ran the calculations (

error.zip

) and for some reason they keep crashing without any error massage in the OUTCAR. When I remove the commands of the dipole section, the calculations proceed smoothly. Can anyone advise on what can I do? or maybe try and reproduce the issue?

Thanks,


Re: Error with running MD calculations with dipole and electric field

Posted: Fri May 09, 2025 1:46 pm
by jonathan_lahnsteiner2

Dear Abdulrahman Allangawi,
I was able to reproduce your error. But when checking your INCAR file carefully I recognized that you are setting the tag

Code: Select all

NELEC    = 534.0000  # Number of valance electrons (use when charge is needed by adding or removing valance electrons)

This seems to be a typo and should be

Code: Select all

NELECT    = 534.0000  # Number of valance electrons (use when charge is needed by adding or removing valance electrons)

After fixing this issue and rerunning your simulation VASP will give you the following error message

Code: Select all

 -----------------------------------------------------------------------------
|                                                                             |
|     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     ###     ###     ###     |
|                                                                             |
|     LDIPOL = .TRUE. must be selected only for cubic supercells, since       |
|     the quadrupole corrections are currently only implemented for this      |
|     specific geometry.                                                      |
|     Please change your box, or set LDIPOL=.FALSE.                           |
|                                                                             |
|       ---->  I REFUSE TO CONTINUE WITH THIS SICK JOB ... BYE!!! <----       |
|                                                                             |
 -----------------------------------------------------------------------------

So the problem is the calculation you are trying to do is not feasible in VASP because quadrupole corrections are only implemented for cubic boxes. I am not quite sure how you are planning to go further. Please let me know if I can assist you any further.

All the best Jonathan


Re: Error with running MD calculations with dipole and electric field

Posted: Sat May 10, 2025 12:01 am
by Abdulrahman_Allangawi

Dear Jonathan,

Thanks for the insight, one option for me is to extend my unit cell and go into a cubic supercell. However, this will increase my computational time considerably.
To my knowledge, simply removing the LDIPOL tag will deem all tags relating to the dipole and electric field useless, is this correct? If so, are there any other approaches around this issue? my goal is to simply apply a field normal to the surface.

Regards,


Re: Error with running MD calculations with dipole and electric field

Posted: Mon May 12, 2025 7:10 am
by jonathan_lahnsteiner2

Dear Abdulrahman Allangawi,

With LDIPOL dipole corrections to the potential and forces are switched on. Please check the LDIPOL-page for further information. The IDIPOL tag tells along which direction the dipole moment is computed for the correction. So yes the tags are coupled to each other and you can not use IDIPOL and DIPOL tag without setting LDIPOL.

All the best Jonathan