Optimizer IOPT=2

[Ammi]

Hello,

Is it possible to run neb directly with the optimizer IOPT=2 even if there are high forces at some images where with nebmake.pl a short distance of about 1.2 Ang between two atoms can be found?

Thanks

[graeme]

Yes, but you may need to set MaxMove to a smallish value to keep the initial steps in the optimization stable.

But better would be to use the nebmake.py script, which will apply the IDPP method and try to keep the bond lengths more constant in your initial band.

[Ammi]

Thanks.

How can we use nebmake.py, there is no information in the online manual? Should we use after nebmake.pl?

[graeme]

no, just run nebmake.py in the same way that you would nebmake.pl - it will apply the IDPP

[Ammi]

OK thanks.

Yes, it gives images with reasonable bond distances.
So, now I will try IOPT=2 with its default settings and see.