AMBER Archive (2003)

Subject: Minimization does not converge.

From: Javier Cuervo (jcuervo_at_sciences.sdsu.edu)
Date: Tue Jun 10 2003 - 22:14:43 CDT

Dear AMBER users,

I got the following message when I am trying to do a minimization( with
amber7):

     .... RESTARTED DUE TO LINMIN FAILURE ...

                    FINAL RESULTS

   NSTEP ENERGY RMS GMAX NAME NUMBER
   1273 -7.8756E+03 7.5693E-03 1.8686E-01 NH2 2774
... [the rest of the usual information]

     ***** REPEATED LINMIN FAILURE *****

The input file I am using is the following:

 minimize structure
 &cntrl
   imin=1, maxcyc=10000,
   cut=300.0, igb=2, gbsa=1,
   ntpr=10, ntx=1, ntb=0,
 &end

This input has worked for other simulations I've ran (althoug I have not
much experience), actually the output above was taken from a "restart" run
I did because I got the same error, the first minimization ran for 5846
steps.

My questions are
 
What means "LINMIN FAILURE"?

The RMS is ~7 exp-3, wich is close the default threshold for stoping
criteria (1x10-4), will be ok take this coordinates and do the
equilibration regardless the error given by sander?

Thank you in advance,

Javier Cuervo
Graduate Student
Computational Sciences Research Center
San Diego State University
(619) 594 1616