Hi everyone, 

I have a simulation cell, containing CNT and polymer. I fixed the positions of CNT atoms and then i tried to apply a NPT dynamic simulation. but I faced the following error:

Dynamics can't apply a barostat with fixed particles.
Removing all particle constraints may allow the barostat to be used

Now, I need some helps. How can we run a NPT dynamic simulation on a system in which some particles are fixed in it? isn't that possible? I know this is a common procedure in MD simulations!

Thanks,
Karan