PPTA (Kevlar) buckling problem during imposing a temperature with ReaxFF

Hello Giacomo,

I used a coordinate file which I made based on X-ray diffraction results by M. Northolt to make my simulation model.


I used charges data from this work and the author of this work is the same person what you mentioned in your e-mail.


I once used the coordinate file from this work but results were not different from what I made from [1].

I attached a few lines of my coordinate file at the end of this e-mail.

I am doing my research referring to these works but I’m not doing exactly the same thing as these works.



I didn’t know the fact about the control file that “for -lg, the only one that I can see in the doc is thb = 0.01 as opposed to 0.001 (default).”

So, I changed my control file and did the same simulation. But I couldn’t get any improvement about the bucking problem.

I am trying to solve this problem by no heating up to 500K or other things but I am not sure whether I can solve this problem.

I will look at my input file and LAMMPS manual again to find any mistakes.

I think doing simple simulations is better as you mentioned, but I don’t have enough time because I have to finish my graduation thesis and I don’t know whether I can do those things.

There is nothing that others can do about that.

Doing research in a hurry carries a much greater risk of mistakes, and you should be aware of it.