Adding pressure to the system

Hi all,

I would like to know how to apply a pressure difference to a group of atoms?

Suppose I have a system of tubes which is periodic in x,y and z dimension, now I’d
like to apply, say, 100 MPa pressure to the tubes along x axis in the both direction,
while apply, 100 Mpa pressure to the tubes along y axis in the both direction so that i can compress the tube. here the tube refers to the system of carbon nanotube and application of pressure is in transverse direction of axis of tube.

Any suggestion is highly appreciated.

Arun

In LAMMPS pressure is only applied to the entire system.

You can use fix npt to run dynamics with an external pressure

and it can be applied differently in different dimensions.

Steve