[lammps-users] MUHAMMAD SAAD ALI

Respected Sir,
Here is my input script file with error in doc fie. I am using LAMMPS-64bit-9Oct2020 on windows 10.
Thanks for cooperation.

Doc1.pdf (186 KB)

in.twolayernew (514 Bytes)

There are two problems I have found in your input script.

  1. There is no clearance between the layers. One layer started from 0 to 20 and the other started immediately from 20 to 35. So when you create a system like this, there will surely be some atom overlap from the beginning and this may lead to very high repulsive forces which can make the simulation unstable causing lost atoms. So I changed the lower layer size along the z axis from 0.5 to 19.5 and upper layer from 20.5 to 34.5.

  2. Your lj potential parameters are not proper. I understand you are not simulating any real material, but still the value of epsilon in your lj parameters is 1. This is very high. This will again cause huge interaction potential values and make the simulation unstable. I have changed it to 0.1.

I think you should work with any real materials, so that your lj parameters are not unrealistic. And always be careful about clearances. Try to visualize your simulation in OVITO or VMD. It will help you to debug your script.

Mahmudul Islam
Mechanical Engineering
Bangladesh University of Engineering and Technology
Website: https://sites.google.com/view/mahmudulislamridul/home

in.twolayernew (524 Bytes)

in.twolayerdia (1 KB)

in.twolayernew (524 Bytes)

in.twolayerdia (1 KB)

in.twolayerdia (1 KB)

Respected Sir,
This is what you picked out last time. By now my questions are separate. What potential can I use eam meam or something else? And please also tell me for making diamond I have used 8 basis atoms with fcc. Or some other data file is better for diamond wet by some alloy?
Thanks for cooperation.

please note that these are not questions about LAMMPS but about how to do your research.
for that you need to talk to your advisor/supervisor and study the published literature.

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