[CPMD-list] Problem doing transition state search

[Jan-Willem Handgraaf]

Dear Tuma,

Due to strong anharmonicities near a transition state, it is often much harder 
to compute than a ordinary minimum. In my experience, the rational function 
optimization algorithm as implemented in CPMD is a somewhat crude optimizer 
and is rather dependent on the choice of the empirical initial Hessian. 
However, your values of the gradients on the ions are already quite small? I 
suspect that you are at the limit of what is possible with this algorithm.

Hope this helps,

Jan-Willem Handgraaf

P.S. I've tested CPMD against the atomic-orbital based ADF package a got a 
very good agreement with respect to transition-state geometries of transition 
metal complexes.

-- 
Jan-Willem Handgraaf
Department of Chemical Engineering
University of Amsterdam
Nieuwe Achtergracht 166
1018 WV Amsterdam
The Netherlands

Room: C6.18
Tel: +31-20-5256492
Fax: +31-20-5255604
Email: jwh at science.uva.nl
Web: http://molsim.chem.uva.nl/