UT theoretical chemistry code forum

Dear Professor,
Could you please answer me the question that should the tag ICHAIN must be set before using your vtsttools? Since when I didn't use tag IOPT, I can still grep the ICHAIN tag in the OUTCAR file. I have read your web page saying that you have a different neb scheme from the primary VASP version, I alse find your code file neb.F, so I guess it is neccessary to set the tag of ICHAIN, but I alse suspect that it would be run by defaunt since I can find the string ICHAIN in the OUTCAR file. So is it neccessary to set ICHAIN to use your tools?
Thank you!

The ICHAIN tag sets the type of calculation that will be run with the VTSTtools. ICHAIN=0, for example, will specify an NEB calculation which can include the climbing image. For optimizers, you can either use the built-in vasp optimizers (with IBRION) or our vtst optimizers (with IOPT).

Thank you for your valuable advice.