Hello everybody,
I’d like to use the NEB package with a reaxFF potential, but I don’t know which timestep should i use for the minimization required. I’ve checked the manual and I found two contradicting advices:
IMPORTANT NOTE: As explained below, a NEB calculation perfoms a damped dynamics minimization across all the replicas. The mimimizer uses whatever timestep you have defined in your input script, via the timestep command. Often NEB will converge more quickly if you use a timestep about 10x larger than you would normally use for dynamics simulations.
The damped dynamics minimizers, such as quickmin and fire), adjust the position and velocity of the atoms via an Euler integration step. Thus you must define an appropriate timestep to use with NEB. Using the same timestep that would be used for a dynamics run of your system is advised.
could anyone explain which one should I use?
thanks in advance
Franco Zanotto
Hello everybody,
I'd like to use the NEB package with a reaxFF potential, but I don't know
which timestep should i use for the minimization required. I've checked the
manual and I found two contradicting advices:
IMPORTANT NOTE: As explained below, a NEB calculation perfoms a damped
dynamics minimization across all the replicas. The mimimizer uses whatever
timestep you have defined in your input script, via the timestep command.
Often NEB will converge more quickly if you use a timestep about 10x larger
than you would normally use for dynamics simulations.
The damped dynamics minimizers, such as quickmin and fire), adjust the
position and velocity of the atoms via an Euler integration step. Thus you
must define an appropriate timestep to use with NEB. Using the same timestep
that would be used for a dynamics run of your system is advised.
could anyone explain which one should I use?
how about starting with the shorter timestep and checking to see, if
you get faster convergence by increasing it?
axel.