I have ran a Nudged Elastic Band (NEB) calculation using QuantumEspresso through Maestro to find the potential transition state. Within Maestro there is an option where you can select for NEB type calculation.

enter image description here

I used 5 images altogether (1 reactant, 1 product, and 3 extrapolated images). I believe that one of the output images (the third one specifically)

enter image description here

is the transition state. However, from my understanding, to verify this is indeed the transition state, one must calculate the vibrational frequency to determine whether there is one negative (hence imaginary) frequency as this indicate that I have a first order saddle point.

How do I do this frequency analysis within Maestro?

Is there an option where I can quickly select one of the output images and run a frequency analysis on it?

I have poke around a bit and found that there is an option to do a phonon calculation, is this the right thing to do?

enter image description here

I just want to determine whether one of the image I have is a transition state. So if there are other ways to do this, I am all ear!

Thank you for you time.

Disclaimer: I am no computational chemist nor an expert with Maestro. So forgive me if whatever I said is wrong and what I asked is naive.

  • 2
    $\begingroup$ Have you done a climbing image NEB? If not, it's probably not really the true transition state if I understand correctly. $\endgroup$ Mar 31, 2021 at 17:46
  • $\begingroup$ I didn't at first but then I did after. There is an option within Maestro to select climbing image. $\endgroup$
    – KAJ226
    Mar 31, 2021 at 18:45
  • $\begingroup$ Is this a crystal or single molecule? Phonons are closely related. $\endgroup$ Apr 1, 2021 at 13:44
  • $\begingroup$ This is a crystal. $\endgroup$
    – KAJ226
    Apr 1, 2021 at 13:52
  • $\begingroup$ Thanks for the clarification, hopefully Tristan Maxson's answer was useful for you! $\endgroup$ Apr 1, 2021 at 16:30

1 Answer 1


Based on what you have said, a phonon calculation is likely what you want. You should see imaginary frequencies in the output if you do infact have a transition state. You may need stricter convergence for the phonon calculation than the geometry relaxation.


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