### Confusion about NEB calculation

Posted:

**Tue Aug 04, 2020 1:12 pm**Dear Professor,

I am a beginner of VASP software.Recently, when I was learning to calculate the energy barrier of the S atom crossing an edge of the Ni55 cluster, several problems appeared.I can’t figure out the reason by myself, So i hope to find suggestions and solutions here.

The problem is that in NEB calculation, the energy of IS and FS is too far from the energy of five images. This is unreasonable. I don’t know what went wrong.Based on the first question, I did a single-point energy test. The energy difference between TS and IS is 0.58 eV, which is reasonable, so I don’t know if which parameter is wrong in the NEB process.At the same time, I also did a frequency verification of the transition state (03), which showed that it was correct, so I was really at a loss as to the reason why the energy barrier was too large. All the data was packed in the attachment compression package.

Hope to get your attention and thank you in advance！

I am a beginner of VASP software.Recently, when I was learning to calculate the energy barrier of the S atom crossing an edge of the Ni55 cluster, several problems appeared.I can’t figure out the reason by myself, So i hope to find suggestions and solutions here.

The problem is that in NEB calculation, the energy of IS and FS is too far from the energy of five images. This is unreasonable. I don’t know what went wrong.Based on the first question, I did a single-point energy test. The energy difference between TS and IS is 0.58 eV, which is reasonable, so I don’t know if which parameter is wrong in the NEB process.At the same time, I also did a frequency verification of the transition state (03), which showed that it was correct, so I was really at a loss as to the reason why the energy barrier was too large. All the data was packed in the attachment compression package.

Hope to get your attention and thank you in advance！