how to convert Materials studio polymer CG model to lammps by msi2lmp

Hello everyone:

Now, I’m doing a research related to simulate polymer by CG(coarse-grained) model, while i make the initial model by MS, and also i use MS inside manager : meocite to calculate the model, but then, i don’t know how to convert this model to lammps data file by msi2lmp tools, so, Does anyone know how to convert? or send me some advice to tell me how to make a polymer CG model for lammps?

Thank you,

Mr. ZIYU CONG
Graduate Student/ Research Assistant

Email:[email protected]…1911…
E338 Nanomaterials Design Lab
Dongguk University, Seoul

Hello everyone:

   Now, I'm doing a research related to simulate polymer by CG(coarse-grained) model, while i make the initial model by MS, and also i use MS inside manager : meocite to calculate the model, but then, i don't know how to convert this model to lammps data file by msi2lmp tools, so, Does anyone know how to convert? or send me some advice to tell me how to make a polymer CG model for lammps?

as indicated in the LAMMPS manual, how to use the msi2lmp tool is
described in the README file accompanying it in the tools/msi2lmp
folder. you need to provide a compatible force field data base file
(*.frc) for your model. a small number of freely available .frc files
are bundled, but most force fields in this format are proprietary and
require a license.

axel.

Thank you for your reply.

Actually, i follow the example whick is included inside the msi2lmp folder, i can convert the data file correctly by msi2lmp.

but, when i compared with the same model in MS and lammps, i found the total energy of model is quite different after geometry optimization,

then, the forcite make my much confused, i don’t know what make these model different with each other, do you have any idea about this question?

Beside the aformentioned question, i found in MS, there has the reaxff force field for Polymer calculation, but, for msi2lmp tool, there has no applicable *.frc film for converting data file,

Then, how can i convert this problem, please remind some ideas to me.

Thank you so much

Mr. ZIYU CONG
Graduate Student/ Research Assistant

Email:[email protected]…1911…
E338 Nanomaterials Design Lab
Dongguk University, Seoul

Thank you for your reply.

  Actually, i follow the example whick is included inside the msi2lmp
folder, i can convert the data file correctly by msi2lmp.

but, when i compared with the same model in MS and lammps, i found the total
energy of model is quite different after geometry optimization,

are you using the latest version of msi2lmp? the current version is 3.9.8

then, the forcite make my much confused, i don't know what make these model
different with each other, do you have any idea about this question?

no, i don't understand what you are asking here.

  Beside the aformentioned question, i found in MS, there has the reaxff
force field for Polymer calculation, but, for msi2lmp tool, there has no
applicable *.frc film for converting data file,

you are not making sense here. reaxff is not a CG model, quite the contrary.
in any case, msi2lmp was written over 10 years ago for the then
current MS program, and any updates since have only been to remain
compatible with how LAMMPS has changed, but not for any newer
features. reaxff is most definitely not supported, since it is neither
a class1 or class2 force field.

axel.