Need assistance in Double wall carbon nanotube(DWCNT) simulation

Hello everyone,

I have done the tensile simulation for single wall carbon nanotube, for that i have generated data file from vmd topotool.

When i was trying to simulate the DWCNT, i could not generate the data file for DWCNT. can anyone tell me the way to generate.

And i dont have idea about how to define the vander walls interaction between the walls of inner and outer nanotubes.