UT theoretical chemistry code forum

graeme wrote:
> Keep that ediffg=-0.01 calculation running - it may still converge.
Dear Professor Graeme,
I am very glad to tell you that the dimer calculation was convergent. Thanks a lot for your suggestions. And the DIMCAR is as below:
Step Force Torque Energy Curvature Angle
1 0.15098 2.41262 ...

Dear Professor Graeme,
Thanks a lot for your reply, I will recalculate this. Have a good day.

Dear Professor Graeme,
I also recalculated the transition state with IVDW=12, and in Cl-NBE calculations, the process went reasonable as before. For the dimer calculations later, the process in the DIMER is better than before, like this:
For ediffg = -0.02:
Step Force Torque Energy Curvature Angle ...

Dear Professor Graeme,
Thank you for your reply. I will recalculate the TS3. And I am still confused about the thing that the content in DIMCAR does not update when finishing the first step. Is this a normal phenomenon?

Dear Professor Graeme,
Maybe you should use the passwords to decompress the file. The password of this file has been sent to your email. Thank you a lot for your reply.

Dear Professor Graeme,
Thanks a lot for your suggestions, I tested the parameter “DRotMax” on the dimer calculations and the calculation files have been attached. In the TS1 file, when I set DROTMAX=10, the structure reached the required convergence criteria on step2. When I set DROTMAX=30, the ...

Dear Professor Graeme,
Oh, I got your words, thanks a lot for your reply :)

Dear Professor Graeme, there is still a problem puzzling me. Is this reasonable that "Torque" doesn't stop until reaching max rotating steps, in other words, doesn't converge for IOPT=1 dimer calculations? Looking forward to your reply.

Dear Professor Graeme,
Thanks a lot for your analysis and solution. I now totally agree with your views that it's reasonable for the process and results with IOPT=1. Thanks again for your explications. The calculating files will be reuploaded with no password after finishing the subject.

Dear Professor Graeme,
Thanks a lot for your reply. The files about these two calculations are attached. And there are other attached files about processed POSCAR in which we constant some atoms coordinate for your analysis. Because of the unpublished work, the password will be sent to your mail ...

This is the DIMCAR with EDIFFG = -0.01 and DRotMax = 10:
Step Force Torque Energy Curvature Angle
1 0.05496 4.29851 -242.71845 -0.06107 14.48730
1 0.05496 5.08602 -242.71845 0.52032 9.36333
1 0.05496 2.85052 -242.71845 -0.36601 8.30124
1 0.05496 3.57028 -242.71845 -0.27680 12.64568
1 0.05496 4 ...

Dear Professor Graeme,
Thanks a lot for your reply. In the 'IOPT=1' dimer calculation, I set EDIFF = 1E-7 and EDIFFG = -0.01. For dimer parameters, I set ICHAIN = 2,DdR = 0.005,DRotMax = 6,DFNMin = 0.01,DFNMax = 1.0,IOPT = 1. We can see in DIMCAR file that calculation stoped with FORCE larger than 0 ...

Dear all,
I am running the DIMER method to get the transition state. The ClNEB ahead converged well. But the DIMER method did not converge. The system I work with is the atoms migrate across the crystals. When I set IOPT=2, the DIMCAR was like this:
Step Force Torque Energy Curvature Angle
1 0 ...

Here is the parameters of cNBE and DIMER calculations:
cNEB Parameters
ISTART = 0 (Read existing wavefunction; if there)
ISPIN = 2 (Non-Spin polarised DFT)
MAGMOM = 41*3
ICHARG = 2 (Non-self-consistent: GGA/LDA band structures)
LREAL = Auto (Projection operators: automatic)
ENCUT = 520 (Cut-off ...

[quote=graeme post_id=21486 time=1630451100 user_id=2]
I did a couple of subsequent calculations and I believe that the dimer calculation has originated near a shoulder in the potential. On a shoulder, there is a negative mode, but when you follow it, it can disappear. Try getting closer with the ...