Saturday, January 2, 2010

Common error messages in GAMESS: Failure to locate stationary point

***** FAILURE TO LOCATE STATIONARY POINT, TOO MANY STEPS TAKEN *****
  UPDATED HESSIAN, GEOMETRY, AND VECTORS WILL BE PUNCHED FOR RESTART
**** THE GEOMETRY SEARCH IS NOT CONVERGED! ****
This error message was produced by the following input file. Can you see what's wrong?
$contrl runtyp=optimize icharg=1 $end
 $basis gbasis=pm3 $end
 $data
Title
C1
N     7.0    -0.39094     1.95659     0.14008
H     1.0     0.38874     1.60529    -0.40413
H     1.0    -0.08386     2.76975     0.70945
H     1.0    -0.72485     1.22934     0.80007
H     1.0    -1.14035     2.30329    -0.48754
O     8.0    -0.64579     0.16732     2.03360
H     1.0    -0.26212    -0.73042     2.10569
H     1.0    -1.00756     0.26750     2.93979
O     8.0    -1.80535     3.31298    -1.59619
H     1.0    -1.39440     3.81065    -2.33214
H     1.0    -2.74148     3.57968    -1.71559
O     8.0     0.26578     4.05264     1.54485
H     1.0     1.03270     4.27032     2.11226
H     1.0    -0.26135     4.87344     1.64760
 $end
Actually, there is no problem with the input file as such. A geometry optimization is an iterative process and if the gradient it not below the convergence criteria within 20 steps, GAMESS will stop and print out the message shown above.

The solution is simply to take the last set of coordinates and run the optimization again, as I show in the screencast below.

As I've mentioned in a previous post I think the default criterion for geometry convergence (0.0001) is too strict, and the default number of steps (20) is too small. So I usually use 0.0005 and 50, respectively.
$statpt nstep=50 opttol=0.0005 $end 


11 comments:

http://abebedorespgondufo.blogs.sapo.pt/ said...

Happy New Year 2010.

Anonymous said...

When I get this error message, I open the resulting log file, the one containing the 'error' message, in Avogadro and prepare the geometry optimisation file using the data from the structure that Avogadro returns.

Is this strategy correct? Does Avogadro always return the appropriate structure under these circumstances?

Jan H. Jensen said...

yes

Anonymous said...

thanks! (Really useful blog and book!).

Marta Wisniewska said...

Hello,
I have this same problem. But in my .log file I don't have last set coordinates of my particles (I have the one from input file). I tried get the optimization of geometry throughout mopac calculations (and next use it for GAMESSs' job), but it didn't work. Do you have any idea?

Thank you in advance,
Marta

Jan Jensen said...

i'd need to see the log file

Marta Wisniewska said...

could I send you an e'mail? it is easier to attach file.

Jan Jensen said...

The aim of this blog is to help everyone in an open way so please share the file somehow (figshare, google docs, pastebin, github, ....)

Marta Wisniewska said...

Yes, you have right!
Meantime, I changed structure geometry (I built it again) but I have error again. I attach the file:
http://figshare.com/download/file/1000152/1

I think I must rebuild the structure again.

Thank you in advance,
M.

Jan Jensen said...

What's your question again? It looks like you just ran out of steps.

Marta Wisniewska said...

you have right,
thank you!