I am trying to run a simulation including formic acid (HCOOH) and water (h2O). I want these two kinds of atoms in my system keep rigid during the simulation. However, there is an error when I use the fix shake command. It says “ERROR: shake clusters are connected”. Whether can molecule containing more than 4 atoms be kept rigid in Lammps? I find that “fix rigid” may have this function, but I’m not sure whether it can be used here due to my confusion of the difference between “fix shake” and “fix rigid”.
I am trying to run a simulation including formic acid (HCOOH) and water
(h2O). I want these two kinds of atoms in my system keep rigid during
the simulation. However, there is an error when I use the fix shake
command. It says “ERROR: shake clusters are connected”. Whether can
molecule containing more than 4 atoms be kept rigid in Lammps? I find
that “fix rigid” may have this function, but I'm not sure whether it can be
used here due to my confusion of the difference between “fix shake” and
“fix rigid”.
yes, you can use fix rigid on some atoms and fix shake on others.
the limitations and modus operandi of fix shake are explained at great
length in the manual, same for the fixes in the rigid family.