Dear Graeme,
thank you for your suggestions.
The calculation with displacement=0.001 and EDIFF=1e-7 still gives one additionally negative frequency.
I am still checking the other settings: EDIFF=1E-8 or negative displacement and also run the DYNMAT with a double displacement.
Search found 2 matches
- Fri Mar 04, 2011 6:33 am
- Forum: VTSTTools
- Topic: Frequency calculation with DYNMAT and IBRION=5
- Replies: 3
- Views: 15540
- Thu Mar 03, 2011 4:28 pm
- Forum: VTSTTools
- Topic: Frequency calculation with DYNMAT and IBRION=5
- Replies: 3
- Views: 15540
Frequency calculation with DYNMAT and IBRION=5
Hi all,
I found a transition state with NEB and then optimized the structure with IBRION=1. I used EDIFFG=-0.03. I did not want to use even stricter force criteria, since the optimization needed more than 2000 geometry steps to converge.
I decided to run a Full Hessian calculation (120 atoms = 720 ...
I found a transition state with NEB and then optimized the structure with IBRION=1. I used EDIFFG=-0.03. I did not want to use even stricter force criteria, since the optimization needed more than 2000 geometry steps to converge.
I decided to run a Full Hessian calculation (120 atoms = 720 ...