wall/reflect

no - fix wall/reflect works so far as I know

Steve

Hi Dear Meisam

This Boundary Condition works well, but atom lost error occur when a atom go out of domain , one of the reason is when the atom reflected, distance between two atom become very small and it make a huge force and huge velocity (according to LJ Potential), under this condition atom go out of domain.
you have this alternatives:
1- use small time-step
2- use Thermostat at every time-step

Best
Iman