Dump file after minimizing in a loop

LAMMPS LAMMPS Mailing List Mirror
1

Steve you are right, the problem has to do with the minimization.
I looked at the log file and found this line (after 1 steps of minimization):“Stopping criterion = linesearch alpha is zero”
In the manual it is written:
“Alpha will be 0.0 if the line search could not reduce the energy. Even if alpha is non-zero, if the “max atom move” distance is tiny compared to typical atom coordinates, then it is possible the last iteration effectively caused no atom movement and thus the evaluated energy did not change and the minimizer terminated.”
However, the indentation should have cause a significant change in atoms positions, and in fact the values of the forces (578802.14) prove it.

Step Temp TotEng E_pair ForceUnder[3] ForceAbove[3] z1 z2
0 0 -635871.8 -635871.8 -578801.36 578802.14 42.42047 262.42047
1 0 -635871.8 -635871.8 -578801.36 578802.14 42.42047 262.42047
Loop time of 3.84273 on 8 procs (8 MPI x 1 OpenMP) for 1 steps with 152736 atoms

Minimization stats:
Stopping criterion = linesearch alpha is zero
…

I tried “run 0” before minimization, didn’t help.
How can I fix this problem of minimization?
And even though there is a problem with minimization, why does it influence the dump?

Leon.

2

As the minimize doc page says, the dump will write out the final config of atoms at
the end of the minimize, only if the minimization “converged”. It did not converge,
it exited with essentially an error: line search alpha is zero. That typically happens
b/c you have an ill-formed minimization problem. See the minimize doc page
for various reasons that can occur, e.g. your forces do not match your energy.

Steve