UT theoretical chemistry code forum

Hello Professor,

Thanks for your reply. To clarify, let's say I have a crystal structure of NVPF with 278 atoms, and I want to study the migration of Na ions from a stable structure to a state where this Na ion may leave the cell. I relaxed the initial structure with ISIF = 3 up to 0.01 ev/A and ...

Hello,

I am confused about how CI-NEB works when atoms' coordinates are fixed on POSCAR using F F F. For example, a few examples in the forum relaxed the initial and final structures using ISIF=3, but the transition states made by nebmake.pl have all fixed atoms. Though ISIF=2 is used (degree of ...

Hello Professor,

Any suggestions? I couldn't be able to solve this problem.

Musanna

Hello Professor,

I relaxed the end point using the same setting. However, still the energy barrier seems wrong. Also, the fifth images force and energy are not converging for some reason which is not related to end point relaxation , i think. I am a bit confused now! Can you please a take a look? I ...

Hello Prof. Henkelman,

I added all the files this time. Images 0 to 4 seems converging but image 5 is diverging for some reason. Can you please give your suggestions on this?

My input file is :


SYSTEM = NEB-Calc
ISYM = 0 # switch on symmetry
ISTART = 0
ICHARG = 2
IALGO = 38
#PREC = ACCURATE ...

Dear Prof. Henkelman,

I am confused with the high energy barrier (5 eV). Is it physically possible or i am missing something? Please give your suggestion on it. I am adding the files here.

Thank you very much.
Musanna

Hello Professor,

Thanks for the reply. I checked the movie and the cell was shrinking. I optimized the structure again and added the initial structure here. Though all atoms are not converging below 0.01 ev/A, the free atoms are converging below 0.01ev/A. Should I consider the attached path ...

Hello Professor,

Thanks for the reply. I tried to optimize my initial and final image with a few trials. Though all atoms are not converging below 0.01 ev/A, the free atoms are converging around 0.01ev/A. I attached the plots and files here. Can I use these as reasonable initial bands? Also, for ...

Thanks for the reply. The idea is the atom will be diffused away from the surface. That's why I removed the atom from the final image (atom 22 is deleted in image 11) and relaxed it then. Therefore, can you kindly suggest what should I do next?

Also, the intermediate images are not converging even ...

Dear Professor Graeme Henkelman,

I completed another set of simulations but couldn't interpret the migration barrier plot and why there are multiple saddle points along the path. Can you kindly take a look? I am adding the simulation files and the plot here.

Also using nebefs.pl, the images (1,5,8 ...

Dear Professor Graeme Henkelman,

Thanks for the reply. I am adding the updated simulation with the endpoint here. Still, the NEB plot seems wrong to me. Can you kindly give me some suggestions on it?

Regards,
Musanna

Dear Professor Graeme Henkelman,

Thanks for the reply. I am working on adding the endpoint outcar using the following INCAR
General:
SYSTEM = O deposition on Zn surface
ISTART = 0 !begin from scratch
ICHARG = 2 !Default: ICHARG = 2 , if ISTART=0, the initial charge distribution are the atomic ...

Dear Professor Graeme Henkelman,

Thanks for the reply. I am adding the updated file with folder 11. However, I didn't add the OUTCAR in that as I am confused about how to optimize the endpoint. Is it cell relaxation with ISIF=3?

I am also adding the migration energy barrier plots for the two cases ...

Dear Professor Graeme Henkelman,

I am trying to do a cNEB calculation of the Zn atom. I used 2 different setup ( 1st case: images =5, EDIFFG=-0.1, NSW=500 and 2nd case: images = 10 EDIFFG = -0.01,NSW=2000). The migration energy barrier plots are totally different and don't make any sense to me ...