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What is dE - revisited

Posted: Mon Sep 27, 2021 8:25 pm
by KWH
In an earlier post, there was this answer to the question of the meaning of dE
"dE always refers to some energy difference, but as there are many selfconsistency loops and minimization algorithms, e.g., the ionic relaxation, electronic relaxation, line minimization, and the diagonalization of the Kohn–Sham Hamiltonian, it might not be obvious which energy difference it refers to. A more detailed summary of each relaxation step can be found in the OUTCAR file!"

I am unable to find any reference to dE in the OUTCAR. What should I be looking for?

My problem is that the calculation converges and meets the electronic and force convergence requirements, but dE is huge (like 20). Is this OK or symptomatic of a deeper problem?

Thank you

Re: What is dE - revisited

Posted: Mon Oct 04, 2021 1:59 pm
by andreas.singraber
Hello!

Just for reference, here is the old post: forum/viewtopic.php?f=4&t=18207

In the OUTCAR file you can find the dE information in the line

Code: Select all

...
total energy-change (2. order) : 0.2253527E+02  (-0.1987010E+03)
...
However, this is just one example taken from an MD run.. to give you some useful advice, can you attach the files from your VASP run according to the forum guidelines.

Thank you!

Best,

Andreas Singraber

Re: What is dE - revisited

Posted: Thu Jan 19, 2023 11:02 pm
by KWH
My apologies for taking so long to reply, but I got distracted working with Quantum ATK and with VASP problems where the dE value was not an issue. I have attached CONTCAR, INCAR, KPOINTS, OUTCAR, OSZICAR, and POSCAR files for a more recently run system where dE is of the order of E. You will see from the OUTCAR that the system had reached the desired optimization.

Thank you in advance for your help.