Re: [ESPResSo-users] Error shows particle coordinate out of range

[Owen Hickey]

Hey Uday,

The capping of forces to prevent bad overlaps at the start of simulations is often quite tricky. I find it is helpful to monitor both the minimum distance between particles and the energy:

    puts "# Equilibrating charges step $i"

    set act_min_dist [analyze mindist]

    puts "# step $act_min_dist $i"

    set myenergy [analyze energy]

    set totE [lindex [lindex $myenergy 0] 1]

    set kinE [lindex [lindex $myenergy 1] 1]

    puts "# Energy $totE $kinE"

The minimum distance shouldn't be less than about 0.85 if I recall correctly, and the kinetic energy should be around 1.5 kT per particle (assuming you have set the temperature to one). If both of these quantities are reasonable when you've stopped the force capping then there is probably a problem with the variables you chose for your simulation, such as the potentials, the thermostat or the particle density.

I hope that helps,

Owen

On Thu, Mar 13, 2014 at 11:41 AM, padidela uday <address@hidden> wrote:

Hello everyone,

I had simulated a colloidal system with WCA potential. After equilibrating the system the simulation was crashed and it shows and error

which is shown below.

I tried with smaller time steps and increased the warmup steps of the system, but couldnt get a solution for this problem.

Can you please suggest me?

Thank you

Uday