How to get the spring constant for NEB calculations

[dua.harkishan@yahoo.com]

I am running an NEB calculation where an atom is moved by a distance of about 2.54 angstrom and created 9 images in the linear method with maximum distance between images set to 0.4 angstrom. But I am unable to find the spring constant for the ion movement images in the NEB calculation. How to know the spring constant?

[Anders Blom]

The spring constant is not something you compute or "find", it's an input parameter to the NEB optimization algorithm, and used to keep the images constrained along the NEB path. Its exact value is not terribly important, in my experience, I have never used anything else than the default value 5 eV/Ang.

[dua.harkishan@yahoo.com]

Thank you Anders Blom for your reply!
But how do you know that the Default value is 5 eV/A. From where you get this information? If it is in the ATK manual kindly give me the link of that page please. 

[Anders Blom]

Very important website!
https://docs.quantumatk.com/
https://docs.quantumatk.com/manual/Types/OptimizeNudgedElasticBand/OptimizeNudgedElasticBand.html