Dear Lammps users,
I am trying to study heat transfer through a specifically shaped planar graphene sheet. It has two rectangular segments connected by a very narrow link. The two extreme ends are fixed. I apply three heat baths, two heat baths at the two ends and one heat bath in the middle. The two terminal heat baths are kept at 900 and 110 K.I use NVE for all the non-fixed atoms and use temp rescale for the heat bath atom groups. The temperature of the middle heat bath varies between 200 to 600K.
Now, above a certain threshold temperature for the middle heat bath, typically, above 450 K, two free edges near the middle ( right edge of left rectangle and left edge of right rectangle, below the narrow link) gets attached, as in like, as if new bonds are formed joining the two edges. The edges remain joined even after removal of middle thermostat. I removed the middle thermostat, kept on the two terminal thermostats, and let it run for 8 ns to check if the segments separate but it stays on. I am using AIREBO potential, which according to my knowledge, is capable of dynamically creating of breaking bonds. My question is, does this effect sound physical? This is as if I am welding and joining the two sheets. I know there are MD studies of welding graphene sheets. Is there a theory which can explain this joining effect?
Please let me know if you need further details…
Thanks and regards,