Dear All,
I want to rotate my 2D particle system such as it is placed on a disk which
is rotating with some angular velocity. I have used fix addtorque command but boundary
is creating problem.

what kind of problem? and how?

I want to know which command i use to tackle this problem ?.

there is too little information here to give advice.

If by boundary, you mean periodic boundary, then you can't do it.
Periodic boundaries are fundamentally incompatible with rotating
systems, because angular momentum changes discontinuously each time a
particle is shifted by a periodic cell vector.

If you can construct a non-periodic system, then everything should
work just fine.

One another question is that if i use non-periodic boundary condition then

atoms will loss. How i tackle atoms loss in non-periodic boundary condition.

If by boundary, you mean periodic boundary, then you canâ€™t do it.
Periodic boundaries are fundamentally incompatible with rotating
systems, because angular momentum changes discontinuously each time a
particle is shifted by a periodic cell vector.

If you can construct a non-periodic system, then everything should
work just fine.