how to define different pair potential for two groups of carbons

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1

I want to simulate a graphene sheet inside a carbon nanotube. It seems carbons are all of the same types. However, the potential style of the sheet is different from CNT, I defined them in two different groups. Now I don’t know how to write a command to assign pair coeff. please help me…

2

I want to simulate a graphene sheet inside a carbon nanotube. It seems carbons are all of the same types. However, the potential style of the sheet is different from CNT, I defined them in two different groups. Now I don’t know how to write a command to assign pair coeff. please help me…

there is not enough information here to give any specific information.
some general consideration, though:

  1. why would you want to use different potentials for compounds that can be well represented by a single suitable pair style?
  2. you cannot assign different potentials to groups of atoms defined with the “group” command. those must be labeled with a different atom type number.
  3. if you want to have a different potential for the CNT and the sheet, you don’t need two but three different potentials, since you also need to define how to compute the interactions between atoms that are using the different potential types.
  4. to due different potential types you need to use pair style hybrid. how to use pair style hybrid and how to assign the different settings is explained in great detail in the manual.

axel.