Dear All,
I wish to create a rigid chain for simulation. If I just create 3-4 monomers, I put the command:
inter 0 rigid_bond 3 0.1 0.1
the system may run well with time step 0.001. But if I increase the monomer number, for example 350 monomer, it will produce error:
background_errors 0 {053 RATTLE failed to converge after 1000 iterations} 1 <consent> 2 <consent> 3 <consent> 4 <consent> 5 <consent> 6 <consent> 7 <consent>
After some trial, the system with 350 monomer can run about 400000 steps (then crash again) with the rigid bond command:
inter 0 rigid_bond $rigid_r 0.1 1000000000000000000.
with time step 0.000001!!!, so maybe I should reduce the time step or add <velocity
tolerance> again.
My question:
1. I read somewhere in this mailing list about <positional tolerance>, but what is <velocity tolerance> ? Is it still permitted if I use that huge 1000000000000000000. value for <velocity tolerance>? or I have gotten unphysical result by putting that huge value?
2. For anyone that has their own trick in creating rigid bond in Espresso, I thank for your share.
Thank you,
Agung