[gmx-users] Conjugate Gradient Minimization

[Andrea Hombrecher]

Dear Gromacs-users,

when I run a Conjugate Gradient minimization of a heme containing protein in
water, I get the folowing error message:

Negative w:  -1.994998153216e+12
z=  -1.019267687500e+06
gpa=   1.504767444493e+05, gpb=   2.016195132868e+07
a=   0.000000000000e+00, b=   1.142665837506e-07
EpotA=  -4.397891875000e+05, EpotB=  -4.397883750000e+05
Negative number for sqrt encountered (-1994998153216.000000)
Terminating minimization

writing lowest energy coordinates.

Conjugate Gradients did not converge in 1327 steps
  Potential Energy  = -4.39789e+05
Maximum force:  5.14396e+02

Could anybody tell me, what "w" means, and why it gets negative?

Thanks in advance

Andrea

-- 
Andrea Hombrecher                                                   

Heinrich-Heine-Universitaet Duesseldorf
Institut fuer pharmazeutische Chemie
Gebaeude 26.23
Universitaetsstrasse 1
40225 Duesseldorf

   Tel: 0211-81-13830
   Fax: 0211-81-13847
E-mail: hombr at pharm.uni-duesseldorf.de