weird problem with energy minimization

Please keep the list in the loop.
Comments below.

Steve

Hi Steve:
Thanks a lot for this explanation. I have a few more questions:
1) Can I infer from your words that saving restart file periodically has
much smaller influence on MD than on minimization?

A restart file is just a round-off issue. A minimization is just a
pre-processing
step. Neither have any "influence" on MD per se.

2) You said writing restart files affects ordering of atoms, but I guess
atom types wouldn't be changed. Am I right?

no change in atom types

3) So far I only know how to write a restart file on a periodically. I am
wondering how to set it as only writing the file when a calculation
(minimization) ends.

Use the write_restart command.