When setting IVDW=12, the D3(BJ) dispersion correction is applied. VASP reports the system energy both before and after the dispersion correction is applied. However, from my cursory glance, it appears that the forces are only provided after the dispersion correct is applied. Is there a way to modify the I/O such that VASP also prints out the forces before the dispersion correction is applied?
Reporting of forces before D3(BJ) correction
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asrosen
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christopher_sheldon1
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Re: Reporting of forces before D3(BJ) correction
Hi Asrosen,
Thank you for your question. You are correct that the forces are only available after the dispersion correction is calculated. There is no way to modify the input to print the forces before the dispersion correction. I would suggest running a calculation using the same POSCAR and INCAR, while turning off the dispersion correction (e.g., #IVDW = 12) and performing a single ionic step (NSW = 0). Then the forces and energy will be printed out for your structure without the dispersion correction.
Does this answer your question?
Best wishes,
Chris