Infinite Graphene with explicit bonds causing compressive stresses during straining

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1

Thanks Aidan!

I was applying strain as “change_box all”. My initial thought was the repositioning of the atoms in the graphene sheet will come back to initial positions during the time integration between strain steps due to its finite nature. So the compressions may be due to the time integration is not long enough or the infinite dimension may have affected the repositioning.

However after I change the command to “change_box polymer”, I don’t see any compressions in the graphene sheet.

If I have a finite (in both directions) graphene sheet, is it still a good idea to use "change_box polymer” instead?

Best,

  • A
2

Yes, as a general rule, structures that are finite should not be strained, since the strained structure will be unstable and will relax back to an unstrained state, often in a very surprising way. The compression you were seeing probably was due to tensile stress waves reverberating back and forth across the structure.