Dear LAMMPS developers,
I have noticed from the manual that it is an error to use command minimize with fix shake, which is needed to fix bonds and angles rigid. So my questions are:
- What steps shall i follow in detail to take into account the fix shake during minimization, as said in the manual by using stiff spring constants for bonds or/and angles(pardon me for asking such a fundamental question).
- Is there an alternative way to launch a minimization with the consideration of fix shake?
Thanks for your concern.
sincerely
2011/5/11 tlx0509236.happy <[email protected]...>:
Dear LAMMPS developers,
I have noticed from the manual that it is an error to use command minimize
with fix shake, which is needed to fix bonds and angles rigid. So
my questions are:
1. What steps shall i follow in detail to take into account the fix shake
during minimization, as said in the manual by using stiff spring constants
for bonds or/and angles(pardon me for asking such a fundamental question).
that depends on what you want to do with the minimized configuration.
if you simply need it to start an MD at a lower potential energy, you
can just ignore it, and use minimize anyway and then do your MD.
if the atoms aren't pushed away too far, the shake constraints will
set everything right in the first couple of MD steps.
2. Is there an alternative way to launch a minimization with the
consideration of fix shake?
nothing much. just crank up the force constants by a factor of 100 or more.
axel.